hey u r getting problem in web.xml coz of this url ..
http://java.sun.com/j2ee/dtds/web-app_2_3.dtd ...u copy paste this url to the
web browser..it will display a page..read what it displays and do as it
says...ur prob will be solved...in short use
http://java.sun.com/dtd/web-app_2_3.dtd instead of
http://java.sun.com/j2ee/dtds/web-app_2_3.dtd and u r through...u wont get any
problem..