How to direct reverse proxy requests using wildcard vhosts

view story

http://serverfault.com – I'm interested in running a reverse proxy with 2-3 virtual machines behind it. Each internal server will run multiple virtual hosts, and rather than manually configuring each individual vhost on the proxy (a variety of vhosts come and go too often for this to be practical), I would like to use something which can employ pattern matching in a sequential order to find the appropriate back-end server. For example: Server 1: *.dev.mysite.com Server 2: *.stage.mysite.com Server 3: *.mysite.com, dev.mysite.com, stage.mysite.com, mysite.com Server 4: * In the above configuration, task.dev.mysite (HowTos)