Small problem with some MUI gadgets and key-bindings

[AmigaMance]

Hi.
 I notice that while most string gadgets in various MUI apps responds to key-bindings such control+x, (clears the entire line) some string gadget of a few MUI apps (Wookiechat, for example) doesn't respond. How can i fix this?

[AmigaMance]

I'm not of this, but i think this is a problem related to the betterstring.mcc, which these apps are using. In the betterstring tab of the MUI preferences, press the gadget next to the "Test the power of BetterString here" and a list of all supported key-bindings pops up. Combinations like control+x are not there... But perhaps there is a way to overcome this?