PL on and EF mount is limited mostly to PL zoom lenses. Most primes are to fat and long going into the mount and there is not enough space for them.
foto-akcesoria.com.pl make adaptors and they have a diagram of what will fit:
http://en.foto-akcesoria.com.pl/images/ ... iary_l.jpg
And they have a list of tested lenses here:
http://en.foto-akcesoria.com.pl/index.p ... -canon-eos