I dont know how this happend...
I was AFK with my warrior alt, and then i returned, and saw it 'Has Logged Of' without doing it?! like this:
You will logout in 20 seconds
19seconds
18seconds
17seconds
e.t.c. to 0...
Normally you logout, but i (After 20 min AFK) was still in game.. with Full Rage... then i used some shouts and whirlwinded... and the rage kept going up 2x Bloodrage speed... (2 in second)
Dont know if this helps.. if you find out, code it so blizz doesnt hotfix it Fast... lol