No action for arrow up or down key

[günther <guenther rapp-informatik de>]

Hallo to all

using gtk the cursor jumps to the next entry field with TAB.
As I notice this also happens with the arrow down key.
How can I make that the arrow down key has no function
in my application. For other applications the key should work as
usual, so I will not change xmodmap or things like this.
I want only recognize the key and throw it away with no action

Thanks for help
günther
-- 
R=I+S  Rapp Informatik Systeme GmbH
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