diff --git a/mex/sources/bytecode/testing/mex_interface.cc b/mex/sources/bytecode/testing/mex_interface.cc
index 6a7c508f8..ab16ecd3f 100644
--- a/mex/sources/bytecode/testing/mex_interface.cc
+++ b/mex/sources/bytecode/testing/mex_interface.cc
@@ -321,7 +321,9 @@ mxDuplicateArray(const mxArray *array)
       memcpy(Array->data , array->data, Size);
       break;
     default:
-      mexErrMsgTxt("Array type not handle");
+      ostringstream tmp;
+      tmp << "Array type not handle: " << array->type << "\n";
+      mexErrMsgTxt(tmp.str());
     }
   return(Array);
 }
@@ -421,7 +423,9 @@ read_Array(FILE *fid)
       Array = read_char_array(fid);
       break;
     default:
-      mexErrMsgTxt("Array type not handle in read_Array\n");
+      ostringstream tmp;
+      tmp << "Array type not handle in read_Array: " << array_type << "\n";
+      mexErrMsgTxt(tmp.str());
     }
   return(Array);
 }
diff --git a/mex/sources/bytecode/testing/mex_interface.hh b/mex/sources/bytecode/testing/mex_interface.hh
index 80f819194..ea79bd16a 100644
--- a/mex/sources/bytecode/testing/mex_interface.hh
+++ b/mex/sources/bytecode/testing/mex_interface.hh
@@ -29,6 +29,12 @@
 #include <algorithm>
 using namespace std;
 
+#if !defined(DYN_MEX_FUNC_ERR_MSG_TXT)
+#define DYN_MEX_FUNC_ERR_MSG_TXT(str)           \
+  do {                                          \
+    mexPrintf("%s\n", str);                     \
+  } while(0)
+#endif
 
 typedef unsigned int mwIndex;
 typedef unsigned int mwSize;