Car spoiler.
Yeah, i'm pretty sure he can't claim for loss of earnings from you either as its you taking him to court due to his mistake. If it was the other way round he could stick it on as an additional cost but if he's the defendant he's OBLIGED to appear in front of it... its not optional, he doesn't have a choice.
Paypal sorted a claim out for me a while back... bought a dvd player that turned up DOA. The seller wouldn't do anything so paypal just reversed the money back to my account and told me its up to me what i did with the dvd player. £160 reversed, spent £10 to get it looked at and £20 to get it fixed... £30 later and i had a nice dvd/surround system. They can be good when they are wiling to help.