Cannot start Basic Client

Edit Subject

Hi,

I get the folowing stacktrace when atempting to launch the basic client.
com.sun.deploy.net.JARSigningException: A unsigned post has been found in resource: http://ip..../scrumworks/jnlp/log4j.jar
at com.sun.javaws.security.SigningInfo.getCommonCodeSignersForJar(Unknown Source)
at com.sun.javaws.security.SigningInfo.check(Unknown Source)
at com.sun.javaws.LaunchDownload.checkSignedResourcesHelper(Unknown Source)
at com.sun.javaws.LaunchDownload.checkSignedResources(Unknown Source)
at com.sun.javaws.Launcher.prepareResources(Unknown Source)
at com.sun.javaws.Launcher.prepareAllResources(Unknown Source)
at com.sun.javaws.Launcher.prepareToLaunch(Unknown Source)
at com.sun.javaws.Launcher.prepareToLaunch(Unknown Source)
at com.sun.javaws.Launcher.launch(Unknown Source)
at com.sun.javaws.Main.launchApp(Unknown Source)
at com.sun.javaws.Main.continueInSecureThread(Unknown Source)
at com.sun.javaws.Main$1.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

I am using JRE-version 1.6.0_24-b07

Any ideas?

Best regards
Peter