Mourn said:Didn't we see something about limitations on "sliding" enemies around, in that you can only do it to enemies one size category larger than you, your size, and smaller? It might also apply to grappling.
Grapple - You can attempt a grapple check with anything that is within 1 size category of you. To initiate, you make a Strength Check vs. Reflex Defense. This also doesn't provoke an Opportunity Attack. If you fail, nothing happens. If you succeed, you cause your target to be "Immobilized" for one round. The target can escape his immobilized condition using an Acrobatics or Athletics check. You may move the target 1 square by succeeding on an additional grapple check in the following round.
http://www.enworld.org/showthread.php?t=220310