Problem running Struts 1.2.9 application in Netbeans IDE 6.5.1..?

[Shrikant Deshpande]

I am using NetBeans IDE 6.5.1 with Struts 1.2.9 and Apache Tomcat 6.0.18.

When I try to run the Struts application in NetBeans IDE the following error occurs.

How to resolve this error...? Please help me.

Could not load definitions from resource org/netbeans/modules/java/j2seproject/copylibstask/antlib.xml. It could not be found.
init:
deps-module-jar:
deps-ear-jar:
deps-jar:
Warning: views\pages\calibration\WBCalibration.jsp modified in the future.
Copying 1 file to D:\Caliber Project\CaliberGauges10 Jun2010\build\web
library-inclusion-in-archive:

D:\Caliber Project\CaliberGauges10 Jun2010\nbproject\build-impl.xml:520: Problem: failed to create task or type copyfiles
Cause: The name is undefined.
Action: Check the spelling.
Action: Check that any custom tasks/types have been declared.
Action: Check that any <presetdef>/<macrodef> declarations have taken place.
BUILD FAILED (total time: 0 seconds)

Following is the content of nbproject\build-impl.xml file.

<target depends="init" name="library-inclusion-in-archive" unless="dist.ear.dir">
<copyfiles files="${libs.struts.classpath}" todir="${build.web.dir}/WEB-INF/lib"/>