It's still there!
Patchou merged both features, so you can lock with a password AND hide messenger at the same time
![:)](images/smilies/msn_happy.gif)
Plus! >Preferences > Messenger > Lock Messenger
Edited: Scroll down to find the password field (yeah i know scrollbars in preferences panel are wrong, blame patchou
![8-)](images/smilies/msn_rolleyes.gif)
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