We want to know how we can distribute DRM-protected movies (protected
using RealNetworks Helix) on P2P networks.

The quick answer is just to share them.

Recent legal activity is firming up the opinion that peer to peer
networks are not in themselves illegal, though some of the activities
that take place there do infringe on intellectual property rights.
This makes sense, especially as cars are legal but could be used as
getaway vehicles; and kitchen knives are legal but could be used to
kill people; and so on.

Therefore, if Kazaa or any other P2P network is legal and your
DRM-protected movies are also legal, then just make them available to
people using whichever client you wish.

I presume, however, that you have a more in depth slant to your question?