Java SE (Java Platform, Standard Edition)

Hello,

I started playing around with Web Start and got it running with a simple app, which just shows a empty frame. Now when I tried to run more complex app with libraries I get the error:

java.lang.NoClassDefFoundError: org/apache/commons/httpclient/HttpException
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod(Unknown Source)
at com.sun.javaws.Launcher.executeApplication(Unknown Source)
at com.sun.javaws.Launcher.executeMainClass(Unknown Source)
at com.sun.javaws.Launcher.doLaunchApp(Unknown Source)
at com.sun.javaws.Launcher.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.httpclient.HttpException
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at com.sun.jnlp.JNLPClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 9 more

The HttpException should be in the commons-httpclient.jar listed in the jnlp. My .jnlp file is:

<?xml version="1.0" encoding="UTF-8"?>
<jnlp href="launch.jnlp" spec="1.0+" codebase="https://localhost:8443/mytest/">
	<information>
		<title>MyTest</title>
		<vendor>A Company, Inc.</vendor>
		<description>MyTest</description>
		<description kind="short">MyTest</description>
	</information>
	<update check="always"/>
	<security>
		<all-permissions/>
	</security>
	<resources>
		<!--<j2se version="1.6+"/>-->
		<jar href="MyTest.jar" main="true"/>
		<jar href="lib/MyLibrary.jar"/>
		<jar href="lib/nachocalendar-0.23.jar"/>
		<jar href="lib/antlr.jar"/>
		<jar href="lib/commons-httpclient-contrib.jar"/>
		<jar href="lib/commons-httpclient.jar"/>
		<jar href="lib/commons-logging.jar"/>
		<jar href="lib/commons-transaction-1.0.jar"/>
		<jar href="lib/jakarta-slide-commandline-2.1.jar"/>
		<jar href="lib/jakarta-slide-webdavlib-2.1.jar"/>
		<jar href="lib/jdom-1.0.jar"/>
		<jar href="lib/xml-im-exporter1.1.jar"/>
		<jar href="lib/postgresql-9.1-901.jdbc4.jar"/>
	</resources>
	<application-desc main-class="nt.gui.LoginScreenGUI">
	</application-desc>
</jnlp>

My error is something similar to THIS but the post doesn't seem to have a solution. I'm currently using Tomcat 7 as the webserver and running JDK 1.6.0_31. Any help would be much appreciated. Thanks.