this is great news....i thought i had trodden cat p**/sh** onto my carpet (as one seems to think that under my car is its toilet). Will checkout some aircon cleaner :)
 
I had the same problem with my aircon. Chances are that bacteria is in your a/c system, I bought a can of aircon cleaner from e-bay for about a tenner, followed the instructions and hey presto the smell has now gone!