You are going to need a hash function to store your passwords, and MD5 is (IMHO) decently secure. Moreso than plain old crypt with salt at least. I'm not sure how salt really adds anything useful to the picture - either you have a fixed salt value, in which case it can be ignored as part of the crypt algorithm, or you have a dynamically generated salt value, usually based on some input from the user record or the password itself - which can also pretty much be ignored as part of the crypt algorithm.
It's fairly straightforward how to implement this yourself - check the hashed password against the database for an auth request, hash and store the password when creating a user or changing a password. What else did you need to know?