To reproduce: Go to a local folder with "folder holds a mailing list" ticked in the Mailing List tab of the Folder Properties. Go to another folder which doesn't hold a mailing list. Observe that Message / Mailing-List menu item isn't greyed out, and sub-menu values are for previous folder.
I confirm it.
Git commit cac77f27d0b6c3a64b801c05833e0830b2d7b3c0 by Montel Laurent. Committed on 14/05/2013 at 08:08. Pushed by mlaurent into branch 'KDE/4.10'. Fix Bug 319794 - Mailing-List menu item not greyed out FIXED-IN: 4.10.4 M +1 -0 kmail/kmmainwidget.cpp M +9 -3 kmail/messageactions.cpp M +1 -0 kmail/messageactions.h http://commits.kde.org/kdepim/cac77f27d0b6c3a64b801c05833e0830b2d7b3c0