The "traditional" Windows equivalent would be the Protected Storage subsystem, used by IE (pre IE 7), Outlook Express, and a few other programs. I believe it's encrypted with your login password, which prevents some offline attacks, but once you're logged in, any program that wants to can read it. (See, for example, NirSoft's Protected Storage PassView.)
Windows also provides the CryptoAPI and Data Protection API that might help. Again, though, I don't think that Windows does anything to prevent processes running under the same account from seeing each other's passwords.
It looks like the book Mechanics of User Identification and Authentication provides more details on all of these.
Eclipse (via its Secure Storage feature) implements something like this, if you're interested in seeing how other software does it.