PHP or JavaScript password obfuscator

[ajbritton]

I'm looking for a script that works like this

1 - Input a master password
2 - Inport a secondary password
3 - Combine the two passwords to produce a text string
4 - It should be possible to recovery the secondary password by providing the text string and the master password

I'm sure I've seen something like it somewhere...

[Geoff]

Um, what about XORing the passwords together to generate the text string. Then XORing the secondary password with the text string will result in the master password.

[ajbritton]

That sounds fine, Geoff. I'm really after some ready built code I can just bolt into a web-site.