Modifying the "relief" attribute of a button

Hi.

I'd like that when the mouse pointer hovers over a button, its relief
aspect should be modified, from ~relief=`NONE to ~relief=`NORMAL, and
back when the pointer leaves the button.

Can I do this with the #misc method of my button ? If yes, how ?

Thanks for any help :-)

\bye

-- 

Nicolas FRANCOIS                      |  /\ 
http://nicolas.francois.free.fr       | |__|
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