yes Ben Souther reply is correct. but you can do that in easy way. you don't need to write new servlet. you can have static resources in another webapplication.
below steps may help you to understand better
1) Have all your
jsp's in one web application,lets say 'webapp1'
2) Have your all static source(like images and css files) in another webapplication, lets say 'webapp2'
have directory structure of images and css files in webapp2 like this
webapp2 -> web-inf |->config.xml
|->css ->css files
|->images -> image files
3) deploy both into appserver or web server
4) you can access webapp2 resources in webapp1 like this
/webapp2/images/*.jpg or /webapp2/images/*.css