diff --git a/.gitignore b/.gitignore
index 6feb45057..ff09453b7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -113,8 +113,7 @@ mex/build/matlab/run_m2html.m
 /preprocessor/doc/
 
 # MATLAB dir
-/matlab/dynare_m
-/matlab/dynare_m.exe
+/matlab/preprocessor*
 /matlab/dynare_version.m
 
 # DLL rules
diff --git a/matlab/dynare.m b/matlab/dynare.m
index d72d20787..9cdf8bf37 100644
--- a/matlab/dynare.m
+++ b/matlab/dynare.m
@@ -16,7 +16,7 @@ function dynare(fname, varargin)
 % SPECIAL REQUIREMENTS
 %   none
 
-% Copyright (C) 2001-2014 Dynare Team
+% Copyright (C) 2001-2015 Dynare Team
 %
 % This file is part of Dynare.
 %
@@ -145,7 +145,21 @@ if exist(fname(1:end-4),'dir') && exist([fname(1:end-4) filesep 'hooks'],'dir')
     run([fname(1:end-4) filesep 'hooks/priorprocessing'])
 end
 
-command = ['"' dynareroot 'dynare_m" ' fname] ;
+if ispc
+    [junk, arch] = getenv('PROCESSOR_ARCHITECTURE');
+else
+    [junk, arch] = system('uname -m');
+end
+
+if isempty(strfind(arch, '64'))
+  arch_ext = '32';
+  disp('Using 32-bit preprocessor');
+else
+  arch_ext = '64';
+  disp('Using 64-bit preprocessor');
+end
+
+command = ['"' dynareroot 'preprocessor' arch_ext filesep 'dynare_m" ' fname] ;
 for i=2:nargin
     command = [command ' ' varargin{i-1}];
 end
diff --git a/preprocessor/Makefile.am b/preprocessor/Makefile.am
index aea2e45a7..804282738 100644
--- a/preprocessor/Makefile.am
+++ b/preprocessor/Makefile.am
@@ -69,7 +69,13 @@ DynareBison.cc DynareBison.hh location.hh stack.hh position.hh: DynareBison.yy
 	$(YACC) -o DynareBison.cc DynareBison.yy
 
 all-local:
-	cd ../matlab && $(LN_S) -f $(abs_srcdir)/$(PROGRAMS) $(PROGRAMS)
+	if [ -z "`file $(PROGRAMS) | grep x86.64`" ]; then \
+	  ARCH="32"; \
+	else \
+	  ARCH="64"; \
+	fi; \
+	mkdir -p ../matlab/preprocessor$$ARCH ; \
+	cd ../matlab/preprocessor$$ARCH && $(LN_S) -f $(abs_srcdir)/$(PROGRAMS) $(PROGRAMS)
 
 if HAVE_DOXYGEN
 html-local: