How can I recover a saved account password from Yahoo! Messenger on a Mac?

Question

The Problem

I have a friend who's forgotten their Yahoo account password. They changed it recently and forgot what it was changed to. Fortunately, they have saved the password in Yahoo! Messenger 3.0.1 beta (235554) on their computer. We believe this is the only place where it has been saved. The computer runs Mac OS X 10.7.5. We would like to recover the password for the account, but we haven't found a way to do so yet.

What We've Tried

• Using the account recovery process on the website. They've forgotten the answer to the security question. (It's one of those security question answers that aren't actually correct, making it more secure.) No alternate e-mail address has been associated with the account.
• Viewing the saved password in Keychain. The password appears to be stored in an encrypted or hashed form. (Or perhaps it's a cookie or other unique identifier to send to the server.)
• Finding software to reveal the contents of the password text box in the Yahoo! Messenger UI. I couldn't find any software to do this.
• Using the Sign in to Yahoo! Mail link within Yahoo! Messenger. This provides access Yahoo! Mail for the account, but attempting to access the account information results in a prompt for the password.

Answer 1

I believe this is impossible because I read somewhere that the only thing that is saved on the computer is a non-password identifier to be sent to the server. (It's probably similar to a browser cookie).