Actually, you might want to see the manpages for ssh-keygen and perhaps ssh-agent. Basically you create an RSA key with no password (or use ssh-agent to keep the decrypted key in memory for your process), then run your script without having to deal with the password prompt at all. You'll be using key authentication instead of password auth.

Update: You might also look at Expect, but using a key is generally better than keeping passwords around in crontabs and/or scripts.

--isotope