Deploy Netbeans 6.1 Web Application to Tomcat 5.5

Netbeans 6.1 come bundles with Tomcat 6.0. So you will encounter problem if you upload the war file directly to your production Tomcat 5.5 server.

Reason being the web.xml in you war file use version 2.5 XML declaration but Tomcat 5.5 uses version 2.4. The web.xml is located at
<catalina-home>/webapps/<your apps>/WEB_INF

Look at the first two lines of the web.xml, you shall see something like the following

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">


Whereas in Tomcat 5.5, the two lines shall be replaced with the following

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

After which, you have to clear the cache of compiled JSP file.
<catalina-home>\work\Catalina\<your apps>

Remove the whole folder with name "_" (underscore). This is the compiled JSP file (java class) by tomcat and is compiled only once when the jsp page is accessed/requested for the first time.

You have to stop the tomcat before removing the folder.
The folder will be rebuild automatically after you have restarted the tomcat and the jsp is being accessed.