Well, not so secret anymore.  MMA Weekly confirms the speculation:

According to many insiders, Wanderlei Silva – who also trains at Xtreme Couture and holds two crushing victories over Quinton Jackson while both were fighting for Pride – has been in Griffin’s ear and in his face for the Ultimate Fighter alum’s training camp for this bout. It’s something that Griffin readily confirms and has reaped tremendous confidence from...

He has acquired some fight advice from Wanderlei though. “The one thing he said was immediately grab the head and throw the knee instead of trying to set it up and make the perfect… bam! Grab and go, start throwing, don’t sit there and let him think about it.”

When Silva first came to Xtreme Couture, there were rumors that Forrest was not happy about it, because he thought they would fight eventually, and Forrest does not like to spend time with guys he is going to fight.  In the end however, it may be the time with Silva that puts him over the top in this fight.

Even if he does not intend to use the clinch, this is some pretty effective taunting from Griffin.  Talking about this kind of thing 5 days out from the fight is sure to get into Quinton's head.