I think they could be under Crypto too, regardless of cryptographic weakness. The reason is simply that it's the de-facto place for stuff like that; that's where at least I - without a doubt - would look first.
But if they are to be added to the Crypto module, they should be fixed to follow the same API as the other hash functions though. I think that'd be preferable regardless where in Pike they're added, as well. Besides, the naming convention for functions in Pike is_like_this, and notthisway.