Windows下的Apache Tomcat：更改webapps默认目录

I am deploying my Java application with Ant. Unfortunately my test deployment on the local machine doesn't work because of Vista. The Program Files directionaries are protected and i don't want to start Ant or Eclipse as an Admin. So i had the idea to move my webapps folder to a workspace subfolder, so i can use relative paths in Ant as well.I am deploying my Java application with Ant. Un