The container should recognise the URI automatically from the JAR containing the tag library. So no, you shouldn't need any extra configuration.
For some reason your container isn't recognising the JSTL JAR. Check your paths and file permissions and try again. Also try restarting your container if that causes a problem. Newer containers come installed with JSTL as standard, so also check whether you need the JAR at all. Check the server log to ensure there are no other errors reported.
I usually recommend installing these sorts of JARs into the server lib path rather than that of the individual application. That allows all applications to share the same libraries. Which server and version are you using?
Charles Lyons (SCJP 1.4, April 2003; SCJP 5, Dec 2006; SCWCD 1.4b, April 2004)
Author of OCEJWCD Study Companion for Oracle Exam 1Z0-899 (ISBN 0955160340 / AmazonAmazon UK )
The problem is resolved now. Thanks for your replies.
I was using Tomcat 5.5 integrated with Eclipse IDE. The problem is resolved when I added JSTL related jar files(jstl.jar and standard.jar) in WEB-INF/lib . Previously I included them only in the Java Build path --> Add External Jars ( As I will do for other Jars ). [ December 15, 2008: Message edited by: Thirugnanam Saravanan ]