gtkbuilder and a custom widget under windows

[Andrea Zagli <azagli libero it>]

i made a very simple custom widget (a library) that is gtkbin  
subclass, and it works but...

under gnu/linux it works perfectly, but under windows i couldn't load  
a gtkbuilder xml file that contains the declaration of my widget

i made some test:
- if i load with g_module the library after g_type_init, it loads
- if i load with g_module the library after gtk_init, it gets an error  
(access to an invalid memory address, or something similar, i have in  
italian)

what could be the problem?

ask me more info if you need

thanks in advance