Im aware that there are converters to allow you to use modern controllers - but im wondering how compatible these are . I've always thought the CD32 pad looked ugly and uncomfortable - although i've never used one.
The Amiga/PSX adapter is being sold over on Amibay at the moment, there is an active discussion in the forums, I'm sure somebody there will know regarding CD32 compatibility.
http://www.amibay.com/showthread.php?t=29892