New servlet not picked by JWS !!! HELP

We are using servlets which are throwing html pages using java web server and have oracle as backend for development.
Once if a servlet is run in browser and we change the servlet, the new servlet(.class) is not picked up by the JWS until we stop & start the web-server. We have tried clearing browser's cache, but only starting and stoping the JWS seems to invoke
the new object. Even if we delete the servlet from servlets dir
JWS seems to have a copy of it(earlier version).
To add to the problem, it may sound stupid but this problem
seems to be only occuring on some specific machines.
we r using http://localhost:8080/...../..
Any input is highly valued.