I don't know anything about how the adcom would view this, but I imagine your new employer would be upset with you for taking a new job, knowing you were going to school soon after (assuming they don't know your situation already).

brianm took the words out of my mouth. Also, would it be a move just for the money? I'm not sure how much help a couple month stint at a new employer would look on your post-mba resume...especially if it's a lateral shift. If you're truly not happy then I feel your pain because that can be tough especially knowing that you'll most likely be going to b-school very shortly.