Patch 3.0.3 (04-Nov-2008): No longer triggers global cooldown.
/Patch 2.0.1 (05-Dec-2006): There are now different versions of this spell for different classes.
Patch 1.4.0 (2005-05-05): Now increases base melee attack power by 25% for 15 seconds. When it fades base melee attack power is reduced by 25% for 45 seconds.