In this code line: 

Pixbuf img = new Pixbuf(fitxer);

My Webservice crash, where "fitxer" is an existing jpeg file.

This is the error:

(/usr/share/dotnet/bin/xsp.exe:18588): GLib-GObject-CRITICAL **: gtype.c:2254: initialization assertion failed, use IA__g_type_init() prior to this function

(/usr/share/dotnet/bin/xsp.exe:18588): GLib-GObject-CRITICAL **: g_object_new: assertion `G_TYPE_IS_OBJECT (object_type)' failed

And my xsp version:
xsp.exe 1.0.0.0
(c) 2002,2003 Ximian, Inc.
(c) 2003,2004 Novell, Inc.
Minimalistic web server for testing System.Web