Strange behavior with Linux GTK+ library

[Steve Teale]

I've been trying to add some new methods to ObjectG.d in gtkD. As an example:

        public string getString(string propertyName)
        {
                // void g_object_get(gpointer object, gchar* firstPropertyName, 
... )
                // gchar* is described as being a C style string

                char* csz;
                writefln("%s", propertyName);
                g_object_get(gObject, cast(char*) 
std.string.toStringz(propertyName), &csz);
 // try 1
                //g_object_get(gObject, cast(char*) "font\0".ptr, &csz);
  // try 2
                uint n;
                for (char* p = csz; *p; p++, n++) {}
                return csz[0..n].idup;
        }

When I use this in code to get a property from a GtkTextTag I get a warning
from Glib-GObject telling me there's no such property, and then the expected
result is returned. I've done this several different ways. It works, but with
different warning message string values, like:

font

(thost:9068): GLib-GObject-WARNING **: g_object_get_valist: object class
`GtkTextTag' has no property named `\xb8;\u001a \u0003'
ArtBrush 12

font

(thost:8524): GLib-GObject-WARNING **: g_object_get_valist: object class
`GtkTextTag' has no property named `XO\xdc\u0008\u0003'
ArtBrush 12

This is with DMD2.054. Can anyone hazard a guess as to what's going on here?

Thanks
Steve