diff --git a/Contrib/Library/LibraryLocal/LibraryLocal.cpp b/Contrib/Library/LibraryLocal/LibraryLocal.cpp
index cf43f8eb..ae0f2b3b 100644
--- a/Contrib/Library/LibraryLocal/LibraryLocal.cpp
+++ b/Contrib/Library/LibraryLocal/LibraryLocal.cpp
@@ -103,7 +103,7 @@ int _tmain(int argc, TCHAR* argv[])
 
   // Validate filename
 
-  FILE*fIn = FOPEN(filename.c_str(), _T("rb"));
+  FILE*fIn = FOPEN(filename.c_str(), ("rb"));
   filefound = !!fIn;
   fclose(fIn);
 
@@ -139,7 +139,7 @@ int _tmain(int argc, TCHAR* argv[])
 
   // Write the version to an NSIS header file
 
-  FILE*fHdr = FOPEN(argv[3], _T("wt"));
+  FILE*fHdr = FOPEN(argv[3], ("wt"));
   if (!fHdr) return 1;
 
   // File content is always ASCII so we don't use TCHAR
diff --git a/Source/Plugins.cpp b/Source/Plugins.cpp
index 9b1012ec..db4bbfeb 100644
--- a/Source/Plugins.cpp
+++ b/Source/Plugins.cpp
@@ -72,7 +72,7 @@ namespace {
 // This function slurps the whole file into the vector.
 // Modified so the huge vector isn't returned by value.
 void read_file(const tstring& filename, vector<unsigned char>& data) {
-  FILE*file = FOPEN(filename.c_str(), _T("rb"));
+  FILE*file = FOPEN(filename.c_str(), ("rb"));
 
   if (!file) throw NSISException(_T("Can't open file '") + filename + _T("'"));
 
diff --git a/Source/build.cpp b/Source/build.cpp
index 705d7fd2..cecd9c9e 100644
--- a/Source/build.cpp
+++ b/Source/build.cpp
@@ -2482,7 +2482,7 @@ int CEXEBuild::pack_exe_header()
 
   // write out exe header, pack, read back in, and
   // update the header info
-  FILE *tmpfile=FOPEN(build_packname,_T("wb"));
+  FILE *tmpfile=FOPEN(build_packname,("wb"));
   if (!tmpfile)
   {
     ERROR_MSG(_T("Error: writing temporary file \"%s\" for pack\n"),build_packname);
@@ -2593,7 +2593,7 @@ int CEXEBuild::write_output(void)
     INFO_MSG(_T("\nOutput: \"%s\"\n"), full_path.c_str());
   }
 
-  FILE *fp = FOPEN(build_output_filename,_T("w+b"));
+  FILE *fp = FOPEN(build_output_filename,("w+b"));
   if (!fp)
   {
     ERROR_MSG(_T("Can't open output file\n"));
@@ -3684,7 +3684,7 @@ int CEXEBuild::load_stub()
 }
 
 int CEXEBuild::update_exehead(const tstring& file, size_t *size/*=NULL*/) {
-  FILE *tmpfile = _tfopen(file.c_str(), _T("rb"));
+  FILE *tmpfile = FOPEN(file.c_str(), ("rb"));
   if (!tmpfile)
   {
     ERROR_MSG(_T("Error: opening stub \"%s\"\n"), file.c_str());
diff --git a/Source/icon.cpp b/Source/icon.cpp
index 67983b96..81f62eb8 100644
--- a/Source/icon.cpp
+++ b/Source/icon.cpp
@@ -19,7 +19,7 @@ extern FILE *g_output;
 
 static FILE * open_icon(const TCHAR* filename, IconGroupHeader& igh)
 {
-  FILE* f = FOPEN(filename, _T("rb"));
+  FILE* f = FOPEN(filename, ("rb"));
   if (!f)
     throw runtime_error("can't open file");
 
diff --git a/Source/script.cpp b/Source/script.cpp
index 89c779f4..b61136d3 100644
--- a/Source/script.cpp
+++ b/Source/script.cpp
@@ -2565,7 +2565,7 @@ int CEXEBuild::doCommand(int which_token, LineParser &line)
         int k=line.gettoken_enum(1, _T("all\0IDD_LICENSE\0IDD_DIR\0IDD_SELCOM\0IDD_INST\0IDD_INSTFILES\0IDD_UNINST\0IDD_VERIFY\0IDD_LICENSE_FSRB\0IDD_LICENSE_FSCB\0"));
         if (k<0) PRINTHELP();
 
-        FILE *fui = FOPEN(line.gettoken_str(2), _T("rb"));
+        FILE *fui = FOPEN(line.gettoken_str(2), ("rb"));
         if (!fui) {
           ERROR_MSG(_T("Error: Can't open \"%s\"!\n"), line.gettoken_str(2));
           return PS_ERROR;
@@ -3188,6 +3188,7 @@ int CEXEBuild::doCommand(int which_token, LineParser &line)
     case TOK_P_EXECUTE:
       {
         TCHAR *exec=line.gettoken_str(1);
+        SCRIPT_MSG(_T("!execute: \"%s\"\n"),exec);
 #ifdef _WIN32
         PROCESS_INFORMATION pi;
         STARTUPINFO si={sizeof(STARTUPINFO),};
@@ -3202,7 +3203,6 @@ int CEXEBuild::doCommand(int which_token, LineParser &line)
         system(execfixed);
         my_convert_free(execfixed);
 #endif
-        SCRIPT_MSG(_T("!execute: \"%s\"\n"),exec);
       }
     case TOK_P_ADDINCLUDEDIR:
       {
diff --git a/Source/util.cpp b/Source/util.cpp
index bb35d412..995868f4 100644
--- a/Source/util.cpp
+++ b/Source/util.cpp
@@ -79,7 +79,7 @@ double my_wtof(const wchar_t *str)
 // Returns -3 if the size doesn't match
 // Returns -4 if the bpp doesn't match
 int update_bitmap(CResourceEditor* re, WORD id, const TCHAR* filename, int width/*=0*/, int height/*=0*/, int maxbpp/*=0*/) {
-  FILE *f = FOPEN(filename, _T("rb"));
+  FILE *f = FOPEN(filename, ("rb"));
   if (!f) return -1;
 
   if (fgetc(f) != 'B' || fgetc(f) != 'M') {
@@ -157,17 +157,22 @@ TCHAR *CharPrev(const TCHAR *s, const TCHAR *p) {
   return (TCHAR *) s;
 }
 
-TCHAR *CharNext(const TCHAR *s) {
+char *CharNextA(const char *s) {
   int l = 0;
   if (s && *s)
     l = max(1, mblen(s, MB_CUR_MAX));
-  return (TCHAR *) s + l;
+  return (char *) s + l;
+}
+
+WCHAR *CharNextW(const WCHAR *s) {
+  // BUGBUG: Is this the best we can do?
+  return s + 1;
 }
 
 char *CharNextExA(WORD codepage, const char *s, int flags) {
   char buf[1024];
   snprintf(buf, 1024, "CP%d", codepage);
-  setlocale(LC_CTYPE, buf);
+  const char* orglocct = setlocale(LC_CTYPE, buf);
 
   const char* np;
   int len = mblen(s, strlen(s));
@@ -176,7 +181,7 @@ char *CharNextExA(WORD codepage, const char *s, int flags) {
   else
     np = s + 1;
 
-  setlocale(LC_CTYPE, "");
+  setlocale(LC_CTYPE, orglocct);
 
   return (char *) np;
 }
@@ -300,42 +305,58 @@ BOOL IsValidCodePage(UINT CodePage)
   return TRUE;
 }
 
+#ifdef _UNICODE
+void PathConvertWinToPosix(char*p)
+{
+  if ('\"' == *p) ++p; // Skip opening quote if any (For !system)
+  size_t len = strlen(p);
+
+  /* Replace drive letter X: by /X */
+  if (len >= 2 && ':' == p[1])
+  {
+    p[1] = (char) tolower((int) p[0]);
+    p[0] = '/';
+  }
+
+  do
+  {
+    if ('\\' == *p) *p = '/';
+    p = CharNextA(p);
+  }
+  while (*p);
+}
+#endif
+void PathConvertWinToPosix(TCHAR*p)
+{
+  if (_T('\"') == *p) ++p; // Skip opening quote if any (For !system)
+  size_t len = _tcsclen(p);
+
+  /* Replace drive letter X: by /X */
+  if (len >= 2 && _T(':') == p[1])
+  {
+    p[1] = (TCHAR) tolower((int) p[0]);
+    p[0] = _T('/');
+  }
+
+  do
+  {
+    if (_T('\\') == *p) *p = _T('/');
+    p = CharNext(p);
+  }
+  while (*p);
+}
+
 #define MY_ERROR_MSG(x) {if (g_display_errors) {PrintColorFmtMsg_ERR(_T("%s"), x);}}
 
 TCHAR *my_convert(const TCHAR *path)
 {
-  // TODO: (orip) ref. this func. to use std::string?
   TCHAR *converted_path = _tcsdup(path);
-  size_t len = _tcsclen(path);
-
   if(!converted_path)
   {
     MY_ERROR_MSG(_T("Error: could not allocate memory in my_convert()\n"));
-    return (TCHAR*) path; /* dirty */
+    return 0;
   }
-
-  /* Replace drive letter X: by /X */
-  if(len >= 2)
-  {
-    if (path[1] == _T(':'))
-    {
-      converted_path[0] = _T('/');
-      converted_path[1] = (TCHAR) tolower((int) path[0]);
-    }
-  }
-
-  TCHAR *p = converted_path;
-
-  do
-  {
-    if (*p == _T('\\'))
-    {
-      *p = _T('/');
-    }
-    p = CharNext(p);
-  }
-  while (*p);
-
+  PathConvertWinToPosix(converted_path);
   return converted_path;
 }
 
@@ -352,17 +373,43 @@ int my_open(const TCHAR *pathname, int flags)
   my_convert_free(converted_pathname);
   return result;
 }
-
-FILE *my_fopen(const TCHAR *path, const TCHAR *mode)
-{
-  TCHAR *converted_path = my_convert(path);
-
-  FILE *result = _tfopen(converted_path, mode);
-  my_convert_free(converted_path);
-  return result;
-}
 #endif//!_WIN32
 
+FILE* my_fopen(const TCHAR *path, const char *mode)
+{
+  FILE*f = 0;
+#ifndef _UNICODE
+  f = fopen(path, mode);
+#else
+#ifdef _WIN32
+  TCHAR tmode[20];
+  for (int i=0; ; ++i) if (0 == (tmode[i] = mode[i])) break;
+  f = _wfopen(path, tmode);
+#else
+  const char* orglocct = setlocale(LC_CTYPE, "");
+  const wchar_t* srcW = path;
+  size_t cb = wcsrtombs(0,&srcW,0,0);
+  if (-1 != cb)
+  {
+    char* nativepath = (char*) malloc(++cb);
+    if (nativepath)
+    {
+      cb = wcsrtombs(nativepath,&path,cb,0);
+      if (-1 != cb)
+      {
+        PathConvertWinToPosix(nativepath);
+        f = fopen(nativepath, mode);
+      }
+      free(nativepath);
+    }
+  }
+  setlocale(LC_CTYPE, orglocct);
+#endif
+#endif
+  return f;
+}
+
+
 void *operator new(size_t size) throw(bad_alloc) {
   void *p = malloc(size);
   if (!p)
@@ -579,7 +626,7 @@ static bool GetDLLVersionUsingRE(const tstring& filepath, DWORD& high, DWORD & l
 {
   bool found = false;
 
-  FILE *fdll = FOPEN(filepath.c_str(), _T("rb"));
+  FILE *fdll = FOPEN(filepath.c_str(), ("rb"));
   if (!fdll)
     return 0;
 
diff --git a/Source/util.h b/Source/util.h
index f2f3be73..77e06575 100644
--- a/Source/util.h
+++ b/Source/util.h
@@ -82,9 +82,12 @@ inline void PrintColorFmtMsg_ERR(const TCHAR *fmtstr, ...)
   va_end(val);
 }
 
+
+
 #ifndef _WIN32
 TCHAR *CharPrev(const TCHAR *s, const TCHAR *p);
-TCHAR *CharNext(const TCHAR *s);
+char *CharNextA(const char *s);
+WCHAR *CharNextW(const WCHAR *s);
 char *CharNextExA(WORD codepage, const char *s, int flags);
 int wsprintf(TCHAR *s, const TCHAR *format, ...);
 int WideCharToMultiByte(UINT CodePage, DWORD dwFlags, LPCWSTR lpWideCharStr,
@@ -93,13 +96,16 @@ int WideCharToMultiByte(UINT CodePage, DWORD dwFlags, LPCWSTR lpWideCharStr,
 int MultiByteToWideChar(UINT CodePage, DWORD dwFlags, LPCSTR lpMultiByteStr,
     int cbMultiByte, LPWSTR lpWideCharStr, int cchWideChar);
 BOOL IsValidCodePage(UINT CodePage);
+#ifdef _UNICODE
+#define CharNext CharNextW
+#else
+#define CharNext CharNextA
+#endif
 
 TCHAR *my_convert(const TCHAR *path);
 void my_convert_free(TCHAR *converted_path);
 int my_open(const TCHAR *pathname, int flags);
-FILE *my_fopen(const TCHAR *path, const TCHAR *mode);
 
-#define FOPEN(a, b) my_fopen(a, b)
 #define OPEN(a, b) my_open(a, b)
 
 #else
@@ -107,11 +113,13 @@ FILE *my_fopen(const TCHAR *path, const TCHAR *mode);
 #define my_convert(x) (x)
 #define my_convert_free(x)
 
-#define FOPEN(a, b) _tfopen(a, b)
 #define OPEN(a, b) _topen(a, b)
 
 #endif
 
+FILE* my_fopen(const TCHAR *path, const char *mode);
+#define FOPEN(a, b) my_fopen((a), (b))
+
 // round a value up to be a multiple of 512
 // assumption: T is an int type
 template <class T>