Gtk2::Entry - manipulating key-press-event?

[Martin Junius <mj+gnome ml m-j-s net>]

Hi all!

For a small application using Gtk2::Entry (for input of ISBNs), I want 
the numeric keypad for input of certain other characters (in particular 
the letter 'X' which appears in the checksum of ISBNs) instead of the 
keypad + - * /.

My idea to achieve this is catching key-press-events, checking for 
keypad something, modify the event, and send it on to the application. 
Is this the canonical way to do this? Or is there an easier route?

Regards,
Martin