Problem with jar files

I'm having running a program in my jar. It seems to be a problem with my class path as when I run my jar with this Command line

java -jar ClientTest.jar -h

I get the following error

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/log4j/Logger

at com.company.sub.prototype.mq.services.GenericMQ.<clinit>(GenericMQ.java:23)

at com.company.sub.prototype.mq.services.HeartbeatMessage.<init>(HeartbeatMessage.java:19)

at com.company.sub.prototype.testharness.clientTestHarness.sendHeartbeatMessage(clientTestHarness.java:1263)

at com.company.sub.prototype.testharness.clientTestHarness.runTest(clientTestHarness.java:1195)

at com.company.sub.prototype.testharness.clientTestHarness.main(clientTestHarness.java:1164)

But I know that the log4j-1.2.jar is on my classpath, because if I unpack the jar and run it ,with the same class path, with the following command

java com.company.sub.prototype.testharness.clientTestHarness -h

It works fine. So why wont it run from the jar?

Thanks

Torb

[1109 byte] By [stonest] at [2007-9-30 4:54:41]