ignore modifier

[J S]

Hi,

My users have a problem with the function keys (ie. F1, F2,....) in their X 
application. If the numlock key is off, the function keys work fine. But if 
the numlock key is on, the function keys stop working.
I know they could do xmodmap -e "clear Mod2", however they want to be able 
to use the numpad as well.

Is there a command like IgnoreModifier which you can specify on an 
individual key basis, so I could say for F1 to F12, ignore when the numlock 
key is on?

Thanks for any help.

JS.