Currently Being ModeratedMar 13, 2013 9:19 AM (in response to Glaucoq)
I had something very similar with my Late 2011 MacBook Pro.
It wasn't with the mouse clicker, but that actual mouse pointer not moving for about a few minutes when on the login screen came up. I personally removed this lag by resetting the SMC.
You can do so by following these instructions. http://support.apple.com/kb/ht3964
This may help you, or may not.
You could always try the MacBook Pro discussion to see if anyone in there has had the same problem and managed to resolve it.
Best of Luck