I might have this problem as well. Had the car two weeks now and this afternoon noticed a small river of water running across the passenger footwell mat, the water must have came from above to get onto the mat.
To confuse matters a bit this is the first day since I bought the car that it has rained so cant be sure of the cause. When I bought it the car I thought it ponged a bit inside and that could suggest the carpets have been damp.
Is this aircon drain pipe easily visible (can I check myself to see if it is fitted/connected properly?
Any idea how much a dealer might charge to sort it (assuming he does not need to pull up the carpets etc, just the pipe).