diff --git a/examples/ramst.mod b/examples/ramst.mod
index df4029ad4..90654a4ef 100644
--- a/examples/ramst.mod
+++ b/examples/ramst.mod
@@ -74,8 +74,11 @@ periods 1;
 values 1.2;
 end;
 
-// Deterministic simulation of the model for 200 periods
-simul(periods=200);
+// Prepare the deterministic simulation of the model over 200 periods
+perfect_foresight_setup(periods=200);
+
+// Perform the simulation
+perfect_foresight_solver;
 
 // Display the path of consumption and capital
 rplot c;
diff --git a/license.txt b/license.txt
index 651112b5c..afb06aa4b 100644
--- a/license.txt
+++ b/license.txt
@@ -143,23 +143,24 @@ Copyright: 2005 Henning Schmidt, FCC, henning@fcc.chalmers.se
 License: GPL-3+
 
 Files: matlab/missing/stats/normpdf.m matlab/missing/stats/gamcdf.m
- matlab/missing/stats/common_size.m matlab/missing/stats/chi2inv.m
+ matlab/missing/stats/chi2inv.m
  matlab/missing/stats/gaminv.m matlab/missing/stats/gampdf.m
  matlab/missing/stats/stdnormal_inv.m matlab/missing/stats/betacdf.m
  matlab/missing/stats/betapdf.m matlab/missing/stats/normcdf.m
  matlab/missing/stats/stdnormal_cdf.m matlab/missing/stats/norminv.m
  matlab/missing/stats/stdnormal_pdf.m matlab/missing/stats/betainv.m
+ matlab/missing/stats-matlab/common_size.m
 Copyright: 1995-2007 Kurt Hornik
            2008-2011 Dynare Team
 License: GPL-3+
 
-Files: matlab/missing/stats/quantile.m
+Files: matlab/missing/stats-matlab/quantile.m
 Copyright: 2014-2016 Christopher Hummersone
            2016 Dynare Team
 License: GPL-3+
 
 
-Files: matlab/missing/stats/corr.m
+Files: matlab/missing/stats-matlab/corr.m
 Copyright: 1993-1996 Kurt Hornik
            1996-2015 John W. Eaton
            2013-2015 Julien Bect
diff --git a/matlab/dynare.m b/matlab/dynare.m
index 6c25e1915..e04d24d79 100644
--- a/matlab/dynare.m
+++ b/matlab/dynare.m
@@ -71,16 +71,23 @@ dynareroot = dynare_config('', preprocessoroutput);
 warning_config()
 
 if isoctave
-    if octave_ver_less_than(supported_octave_version)
+    % The supported_octave_version.m file is not in git nor in the source
+    % package, it is manually added in binary packages distributed on dynare.org
+    if exist('supported_octave_version', 'file') && ~strcmp(supported_octave_version, version)
         skipline()
         warning(['This version of Octave is not supported. Consider installing ' ...
-                 'version %s+ of Octave,\notherwise m files will be used instead ' ...
-                 'of precompiled mex files and some features, like solution\n' ...
+                 'version %s of Octave\n' ...
+                 'from www.octave.org, otherwise m files will be used instead ' ...
+                 'of precompiled mex files and some\nfeatures, like solution ' ...
                  'of models approximated at third order, will not be available.'], supported_octave_version())
         skipline()
+    elseif octave_ver_less_than('4.2') % Should match the test in mex/build/octave/configure.ac
+        skipline()
+        warning(['This version of Dynare has only been tested on Octave 4.2 and above. Dynare may fail to run or give unexpected result. Consider upgrading your version of Octave.'])
+        skipline()
     end
 else
-    if matlab_ver_less_than('7.5')
+    if matlab_ver_less_than('7.5') % Should match the test in mex/build/matlab/configure.ac
         skipline()
         warning('This version of Dynare has only been tested on MATLAB 7.5 (R2007b) and above. Since your MATLAB version is older than that, Dynare may fail to run, or give unexpected results. Consider upgrading your MATLAB installation, or switch to Octave.');
         skipline()
diff --git a/matlab/dynare_config.m b/matlab/dynare_config.m
index cbba26268..2e3a2eacd 100644
--- a/matlab/dynare_config.m
+++ b/matlab/dynare_config.m
@@ -79,16 +79,11 @@ p = {'/distributions/' ; ...
 % For functions that exist only under some Octave versions
 % or some MATLAB versions, and for which we provide some replacement functions
 
+% Replacements for rows(), columns(), vec() and issquare() (inexistent under MATLAB)
 if ~isoctave
-    % Replacements for rows(), columns() and issquare() (inexistent under MATLAB)
     p{end+1} = '/missing/rows_columns';
     p{end+1} = '/missing/issquare';
-    % Replacement for vec() (inexistent under MATLAB)
     p{end+1} = '/missing/vec';
-    if ~user_has_matlab_license('statistics_toolbox')
-        % Replacements for functions of the stats toolbox
-        p{end+1} = '/missing/stats/';
-    end
 end
 
 % ordeig() doesn't exist in Octave
@@ -108,6 +103,16 @@ if (isoctave && ~user_has_octave_forge_package('statistics')) ...
     p{end+1} = '/missing/nanmean';
 end
 
+% Replacements for functions of the MATLAB statistics toolbox
+% These functions were part of Octave < 4.4, they are now in the statistics Forge package
+if (isoctave && ~octave_ver_less_than('4.4') && ~user_has_octave_forge_package('statistics')) ...
+        || (~isoctave && ~user_has_matlab_license('statistics_toolbox'))
+    p{end+1} = '/missing/stats/';
+    if ~isoctave
+        p{end+1} = '/missing/stats-matlab/';
+    end
+end
+
 % Check if struct2array is available.
 if ~exist('struct2array')
     p{end+1} = '/missing/struct2array';
diff --git a/matlab/identification_analysis.m b/matlab/identification_analysis.m
index 108945134..768bc5b31 100644
--- a/matlab/identification_analysis.m
+++ b/matlab/identification_analysis.m
@@ -102,6 +102,7 @@ if info(1)==0
             derivatives_info.DOm=dOm;
             derivatives_info.DYss=dYss;
             options_.ar=nlags;
+            options_ident.ar=nlags;
             indJJ = (find(max(abs(JJ'),[],1)>1.e-8));
         end
         if length(indJJ)<nparam
diff --git a/matlab/missing/stats/common_size.m b/matlab/missing/stats-matlab/common_size.m
similarity index 100%
rename from matlab/missing/stats/common_size.m
rename to matlab/missing/stats-matlab/common_size.m
diff --git a/matlab/missing/stats/corr.m b/matlab/missing/stats-matlab/corr.m
similarity index 100%
rename from matlab/missing/stats/corr.m
rename to matlab/missing/stats-matlab/corr.m
diff --git a/matlab/missing/stats/quantile.m b/matlab/missing/stats-matlab/quantile.m
similarity index 100%
rename from matlab/missing/stats/quantile.m
rename to matlab/missing/stats-matlab/quantile.m
diff --git a/matlab/modules/dseries b/matlab/modules/dseries
index bdf42bec7..2bebeef16 160000
--- a/matlab/modules/dseries
+++ b/matlab/modules/dseries
@@ -1 +1 @@
-Subproject commit bdf42bec7bda894e2591d8bebb9fe25423ada4f7
+Subproject commit 2bebeef16f87f215f4c1fed510e243f82dbd67aa
diff --git a/matlab/optimization/dynare_minimize_objective.m b/matlab/optimization/dynare_minimize_objective.m
index 025d41189..b51617010 100644
--- a/matlab/optimization/dynare_minimize_objective.m
+++ b/matlab/optimization/dynare_minimize_objective.m
@@ -135,11 +135,7 @@ switch minimizer_algorithm
         simulated_annealing(objective_function,start_par_value,sa_options,LB,UB,varargin{:});
   case 3
     if isoctave && ~user_has_octave_forge_package('optim')
-        try
-            pkg load optim
-        catch
-            error('Optimization algorithm 3 requires the optim package')
-        end
+        error('Optimization algorithm 3 requires the optim package')
     elseif ~isoctave && ~user_has_matlab_license('optimization_toolbox')
         error('Optimization algorithm 3 requires the Optimization Toolbox')
     end
diff --git a/matlab/perfect-foresight-models/linear_perfect_foresight_problem.m b/matlab/perfect-foresight-models/linear_perfect_foresight_problem.m
index 78d9fed41..3a04ea8e1 100644
--- a/matlab/perfect-foresight-models/linear_perfect_foresight_problem.m
+++ b/matlab/perfect-foresight-models/linear_perfect_foresight_problem.m
@@ -55,9 +55,9 @@ for it = maximum_lag+(1:T)
     z(jexog) = transpose(exo_simul(it,:));
     residuals(i_rows) = dynamicjacobian*z;
     if nargout == 2
-        if it == 2
+        if it == maximum_lag+1
             JJacobian(i_rows,i_cols_J1) = dynamicjacobian(:,i_cols_1);
-        elseif it == T + 1
+        elseif it == maximum_lag+T
             JJacobian(i_rows,i_cols_J(i_cols_T)) = dynamicjacobian(:,i_cols_T);
         else
             JJacobian(i_rows,i_cols_J) = dynamicjacobian(:,i_cols_j);
diff --git a/matlab/perfect-foresight-models/perfect_foresight_mcp_problem.m b/matlab/perfect-foresight-models/perfect_foresight_mcp_problem.m
index eb898322d..000fff50f 100644
--- a/matlab/perfect-foresight-models/perfect_foresight_mcp_problem.m
+++ b/matlab/perfect-foresight-models/perfect_foresight_mcp_problem.m
@@ -74,7 +74,7 @@ i_rows = 1:ny;
 offset = 0;
 i_cols_J = i_cols;
 
-for it = 2:(T+1)
+for it = maximum_lag+(1:T)
     if nargout == 1
         res = dynamic_function(YY(i_cols),exo_simul, params, ...
                                steady_state,it);
@@ -83,15 +83,15 @@ for it = 2:(T+1)
         [res,jacobian] = dynamic_function(YY(i_cols),exo_simul, params, ...
                                           steady_state,it);
         residuals(i_rows) = res(eq_index);
-        if it == 2
+        if it == maximum_lag+1
             [rows,cols,vals] = find(jacobian(eq_index,i_cols_1));
             iJacobian{1} = [offset+rows, i_cols_J1(cols), vals];
-        elseif it == T + 1
+        elseif it == maximum_lag+T
             [rows,cols,vals] = find(jacobian(eq_index,i_cols_T));
             iJacobian{T} = [offset+rows, i_cols_J(i_cols_T(cols)), vals];
         else
             [rows,cols,vals] = find(jacobian(eq_index,i_cols_j));
-            iJacobian{it-1} = [offset+rows, i_cols_J(cols), vals];
+            iJacobian{it-maximum_lag} = [offset+rows, i_cols_J(cols), vals];
             i_cols_J = i_cols_J + ny;
         end
         offset = offset + ny;
diff --git a/matlab/perfect-foresight-models/perfect_foresight_problem.m b/matlab/perfect-foresight-models/perfect_foresight_problem.m
index a4df03f80..c6c6f77a7 100644
--- a/matlab/perfect-foresight-models/perfect_foresight_problem.m
+++ b/matlab/perfect-foresight-models/perfect_foresight_problem.m
@@ -71,22 +71,22 @@ i_rows = 1:ny;
 i_cols_J = i_cols;
 offset = 0;
 
-for it = 2:(T+1)
+for it = maximum_lag+(1:T)
     if nargout == 1
         residuals(i_rows) = dynamic_function(YY(i_cols),exo_simul, params, ...
                                              steady_state,it);
     elseif nargout == 2
         [residuals(i_rows),jacobian] = dynamic_function(YY(i_cols),exo_simul, params, ...
                                                         steady_state,it);
-        if it == 2
+        if it == maximum_lag+1
             [rows,cols,vals] = find(jacobian(:,i_cols_1));
             iJacobian{1} = [offset+rows, i_cols_J1(cols), vals];
-        elseif it == T + 1
+        elseif it == maximum_lag+T
             [rows,cols,vals] = find(jacobian(:,i_cols_T));
             iJacobian{T} = [offset+rows, i_cols_J(i_cols_T(cols)), vals];
         else
             [rows,cols,vals] = find(jacobian(:,i_cols_j));
-            iJacobian{it-1} = [offset+rows, i_cols_J(cols), vals];
+            iJacobian{it-maximum_lag} = [offset+rows, i_cols_J(cols), vals];
             i_cols_J = i_cols_J + ny;
         end
         offset = offset + ny;
diff --git a/matlab/perfect-foresight-models/private/initialize_stacked_problem.m b/matlab/perfect-foresight-models/private/initialize_stacked_problem.m
index 014bb9acb..0f14b2367 100644
--- a/matlab/perfect-foresight-models/private/initialize_stacked_problem.m
+++ b/matlab/perfect-foresight-models/private/initialize_stacked_problem.m
@@ -67,9 +67,9 @@ elseif (options.solve_algo == 11)
     end
 end
 
-y0 = endogenousvariables(:,1);
-yT = endogenousvariables(:,periods+2);
-z = endogenousvariables(:,2:periods+1);
+y0 = endogenousvariables(:,M.maximum_lag);
+yT = endogenousvariables(:,M.maximum_lag+periods+1);
+z = endogenousvariables(:,M.maximum_lag+(1:periods));
 illi = M.lead_lag_incidence';
 [i_cols, junk,i_cols_j] = find(illi(:));
 illi = illi(:,2:3);
diff --git a/matlab/perfect-foresight-models/solve_stacked_problem.m b/matlab/perfect-foresight-models/solve_stacked_problem.m
index 8f033bbf6..3a1e2e715 100644
--- a/matlab/perfect-foresight-models/solve_stacked_problem.m
+++ b/matlab/perfect-foresight-models/solve_stacked_problem.m
@@ -69,7 +69,7 @@ else
     check = 1;
 end
 
-endogenousvariables = [y0 reshape(y, M.endo_nbr, options.periods) yT];
+endogenousvariables(:, M.maximum_lag+(1:options.periods)) = reshape(y, M.endo_nbr, options.periods);
 
 if check
     info.status = false;
diff --git a/matlab/supported_octave_version.m b/matlab/supported_octave_version.m
deleted file mode 100644
index 97e2c4605..000000000
--- a/matlab/supported_octave_version.m
+++ /dev/null
@@ -1,20 +0,0 @@
-function v = supported_octave_version()
-
-% Copyright (C) 2017 Dynare Team
-%
-% This file is part of Dynare.
-%
-% Dynare is free software: you can redistribute it and/or modify
-% it under the terms of the GNU General Public License as published by
-% the Free Software Foundation, either version 3 of the License, or
-% (at your option) any later version.
-%
-% Dynare is distributed in the hope that it will be useful,
-% but WITHOUT ANY WARRANTY; without even the implied warranty of
-% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-% GNU General Public License for more details.
-%
-% You should have received a copy of the GNU General Public License
-% along with Dynare.  If not, see <http://www.gnu.org/licenses/>.
-
-v = '4.2.1';
\ No newline at end of file
diff --git a/matlab/user_has_octave_forge_package.m b/matlab/user_has_octave_forge_package.m
index 07d918d42..a3f1bc38d 100644
--- a/matlab/user_has_octave_forge_package.m
+++ b/matlab/user_has_octave_forge_package.m
@@ -20,4 +20,11 @@ function [hasPackage] = user_has_octave_forge_package(package)
 
 [desc,flag] = pkg('describe', package);
 
-hasPackage = isequal(flag{1,1}, 'Loaded');
+if isequal(flag{1,1}, 'Not installed')
+    hasPackage = 0;
+else
+    if isequal(flag{1,1}, 'Not loaded')
+        pkg('load', package);
+    end
+    hasPackage = 1;
+end
diff --git a/mex/build/matlab/configure.ac b/mex/build/matlab/configure.ac
index 668706229..40e93d6f8 100644
--- a/mex/build/matlab/configure.ac
+++ b/mex/build/matlab/configure.ac
@@ -34,6 +34,7 @@ if test "x$ax_enable_matlab" = "xyes"; then
 
   if test "x$ax_matlab_version_ok" = "xyes"; then
     AX_MEXOPTS
+    AX_COMPARE_VERSION([$MATLAB_VERSION], [lt], [7.5], [AC_MSG_ERROR([Your MATLAB is too old, please upgrade to version 7.5 (R2007b) at least.])])
   fi
 
   CFLAGS="$MATLAB_CFLAGS"
diff --git a/preprocessor b/preprocessor
index a30f8f365..84c2dc5f3 160000
--- a/preprocessor
+++ b/preprocessor
@@ -1 +1 @@
-Subproject commit a30f8f365e89b9520fa44caa6c3c1c288c0adbba
+Subproject commit 84c2dc5f3621d47407397d519b623eb9d1fc1eb3
diff --git a/tests/deterministic_simulations/rbc_det.mod b/tests/deterministic_simulations/rbc_det.mod
index 71fdbd59f..1454609c0 100644
--- a/tests/deterministic_simulations/rbc_det.mod
+++ b/tests/deterministic_simulations/rbc_det.mod
@@ -17,7 +17,7 @@ sigma2  =   0;
 model;
 
   // Eq. n°1:
-  efficiency = rho*efficiency(-1) + EfficiencyInnovation;
+  efficiency = rho*efficiency(-1) + EfficiencyInnovation(-2); // Use a lag of two to test the maximum_lag logic
 
   // Eq. n°2:
   Efficiency = effstar*exp(efficiency);
diff --git a/tests/deterministic_simulations/rbc_det_stack_solve_algo_7.mod b/tests/deterministic_simulations/rbc_det_stack_solve_algo_7.mod
index a4c829ffb..baf60baf2 100644
--- a/tests/deterministic_simulations/rbc_det_stack_solve_algo_7.mod
+++ b/tests/deterministic_simulations/rbc_det_stack_solve_algo_7.mod
@@ -17,7 +17,7 @@ sigma2  =   0;
 model;
 
   // Eq. n°1:
-  efficiency = rho*efficiency(-1) + EfficiencyInnovation;
+  efficiency = rho*efficiency(-1) + EfficiencyInnovation(-2); // Use a lag of two to test the maximum_lag logic
 
   // Eq. n°2:
   Efficiency = effstar*exp(efficiency);