I try to run interest jboss example.
When I execute:c: ant intro-interest-jar
I got this:
Ant version 1.3 compiled on March 2 2001

Buildfile: build.xml
Detected Java Version: 1.3
Detected OS: Windows 2000
parsing buildfile C:\jboss-example\examples\build\build.xml with URI = file:C:/j
boss-example/examples/build/build.xml
Project base dir set to: C:\jboss-example\examples
[property] Loading Environment env.
Build sequence for target `intro-interest-jar' is [validate-servlet, validate-jb
oss, fail_if_not_valid, init, intro-interest-jar]
Complete build sequence is [validate-servlet, validate-jboss, fail_if_not_valid,
init, intro-interest-jar, cmp-cd-upload, cmp-cd-remove, cmp-cd-list, jms-hello-
topic, main, intro-interest-client, clean, dist, jms-destroy-dest25, jms-hello-p
ublisher25, jms-destroy-dest, jms-hello-topic-durable, howto-appletclient-jar, i
ntro-interest-deploy, howto-javamail-deploy-ear, howto-appletclient-compile, jms
-hello-queue-bmt, howto-appletclient-client, jms-create-dest, jms-topic-hello24,
jms-hello-sender, jms-topic-hello22, intro-interest-compile, jms-hello-listener
, cmp-cd-compile, howto-javamail-compile, jms-hello-receiver, howto-appletclient
-deploy, howto-javamail-client, jms-hello-topic-fullconf, jms-hello-receiver25,
jms-manual-jndi, jms-hello-sender25, jms-compile, howto-javamail-deploy, jms-hel
lo-queue, jms-hello-subscriber25, jms-hello-subscriber, cmp-cd-dist, jms-create-dest25, intro-interest-ear, howto-javamail-jar, jms-hello-publisher, cmp-jaws-compile, jms-build]

validate-servlet:
[available] Unable to find file C:\JBoss-2.4.4_Tomcat-4.0.1\jboss\..\tomcat\lib\
servlet.jar to set property servlet.jar
[available] Unable to find file C:\JBoss-2.4.4_Tomcat-4.0.1\jboss\..\jetty\lib\j
avax.servlet.jar to set property servlet.jar
[available] Unable to find file C:\JBoss-2.4.4_Tomcat-4.0.1\catalina\lib\servlet
.jar to set property servlet.jar
[property] Override ignored for servlet.jar

BUILD FAILED

C:\jboss-example\examples\build\build.xml:36: Could not create task of type: path. Common solutions are to use taskdef to declare your task, or, if this is an optional task, to put the optional.jar in the lib directory of your ant installation (ANT_HOME).

Total time: 1 second

I can't figure out what's wrong.
I can start Tomcat and jboss.

Please give me some tips,thanks

Liying