Callback Parameters are Switched

[dhk <dhkuhl optonline net>]

I'm using glade for a front end which has a button that when clicked 
passes a notebook as the user_data to the callback.

I'm using the gdb debugger to look at the two parameters in the callback 
and they are switched.  The first parameter, the button, is the notebook 
object and the second parameter, the user_data, is the button object. 
If I don't use user_data in Glade the parameter are correct, the first 
is the button and the second is NULL.

Why is this happening?

Thanks,
Dave