Most likely you'll need to ask for an updated trainer for the DLC, which doesn't make much sense seeing as the DLC I have is only for weapons and 2 vehicles (and two multiplayer maps but I'm guessing your trainer isn't going anywhere near those) but maybe you have other DLC or maybe the DLC changed the version of the game itself.
PS: I have not downloaded the trainer for this game, nor do I have it installed right now so I will not be able to check if it works on my game, sorry.
[Edited by ArchDuke, 7/8/2011 3:46:51 AM]
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