Yeah, my father in-law did it on my 280e. I'm not exactly sure how he did it, but I think he attached a timer\relay thingy to the pump. It is then activated by the lock\unlock of a remote control central locking unit we installed, telling the pump to run for 5-10 secs (enough time for doors to lock\unlock).
Email me if your interested and I'll see if I can get my father-in-law to sketch out the exact details.
BenzWorld.org forum is one of the largest Mercedes-Benz owner websites offering the most comprehensive collection of Mercedes-Benz information anywhere in the world. The site includes MB Forums, News, Galleries, Publications, Classifieds, Events and much more!