FVWM: how to escape F1?

Hi folks,

I have defined several function keys for fvwm, but sometimes I
would like to send F1 (for example) to the app running in the
window, bypassing fvwm's function bound to it.

Is there some hidden function to temporarily disable the
Key bindings to forward *any* key combination to the window
with input focus?

Hopefully I wasn't too blind to see. Every helpful comment is
highly appreciated.


Regards
Harri