diff --git a/include/wx/string.h b/include/wx/string.h
index 3dae84626a..7969657cc3 100644
--- a/include/wx/string.h
+++ b/include/wx/string.h
@@ -321,6 +321,8 @@ public:
     // (default value of wxSTRING_MAXLEN means take all the string)
   wxString(const wxChar *psz, size_t nLength = wxSTRING_MAXLEN)
     { InitWith(psz, 0, nLength); }
+  wxString(const wxChar *psz, wxMBConv& WXUNUSED(conv), size_t nLength = wxSTRING_MAXLEN)
+    { InitWith(psz, 0, nLength); }
 
 #if wxUSE_UNICODE
     // from multibyte string
@@ -334,13 +336,10 @@ public:
     // from C string (for compilers using unsigned char)
   wxString(const unsigned char* psz, size_t nLength = wxSTRING_MAXLEN)
     { InitWith((const char*)psz, 0, nLength); }
-    // from multibyte string
-  wxString(const char *psz, wxMBConv& WXUNUSED(conv) , size_t nLength = wxSTRING_MAXLEN)
-    { InitWith(psz, 0, nLength); }
 
 #if wxUSE_WCHAR_T
     // from wide (Unicode) string
-  wxString(const wchar_t *pwz);
+  wxString(const wchar_t *pwz, wxMBConv& conv = wxConvLibc);
 #endif // !wxUSE_WCHAR_T
 
     // from wxCharBuffer
diff --git a/src/common/string.cpp b/src/common/string.cpp
index bd4dc94a62..7ab0612f65 100644
--- a/src/common/string.cpp
+++ b/src/common/string.cpp
@@ -341,15 +341,15 @@ wxString::wxString(const char *psz, wxMBConv& conv, size_t nLength)
 
 #if wxUSE_WCHAR_T
 // from wide string
-wxString::wxString(const wchar_t *pwz)
+wxString::wxString(const wchar_t *pwz, wxMBConv& conv)
 {
   // first get necessary size
-  size_t nLen = pwz ? wxWC2MB((char *) NULL, pwz, 0) : 0;
+  size_t nLen = pwz ? conv.WC2MB((char *) NULL, pwz, 0) : 0;
 
   // empty?
   if ( (nLen != 0) && (nLen != (size_t)-1) ) {
     AllocBuffer(nLen);
-    wxWC2MB(m_pchData, pwz, nLen);
+    conv.WC2MB(m_pchData, pwz, nLen);
   }
   else {
     Init();