Error when launching ADOM II

Windows 7 ultimate 64 bit, Firefox 17.0.1, Java 7 update 10.


JNLPException[category: Launch File Error : Exception: null : LaunchDesc:
<jnlp spec="1.0+" codebase="http://www.adom.de/adom-ii/downloads/javawebstart" href="adom-ii.jnlp">
<information>
<title>ADOM II: Legends of Ancardia (powered by JADE)</title>
<vendor>Thomas Biskup</vendor>
<homepage href="http://www.adom.de/"/>
<description>
ADOM II: Legends of Ancardia is the successor to ADOM
(Ancient Domains Of Mystery). It is a so-called roguelike game that
provides access to a huge randomly generated fantasy world in which
you can fight for fame and riches, search artifacts or even challenge
the gods themselves. That is if you don't just want to become a farmer
or a merchant. A whole universe awaits you... welcome to the world of
Ancardia!
</description>
<description kind="short">
ADOM II, a roguelike game and the successor to ADOM, allows you to experience unlimited adventures
in the world of Ancardia. Start your trip into a whole new dimension right away!
</description>
<icon href="adom-ii-icon.png" kind="default"/>
<shortcut online="false">
<desktop/>
</shortcut>
<offline-allowed/>
</information>
<security>
<all-permissions/>
</security>
<update check="always" policy="prompt-update"/>
<resources>
<j2se version="1.6.0_25+" href="http://java.sun.com/products/autodl/j2se" max-heap-size="768m"/>
<jar href="adom-ii.jar" main="true" version="0.3.1"/>
<jar href="j2-commons-cli.jar" version="1.0"/>
<jar href="j2-commons-io.jar" version="1.2"/>
<jar href="j2-commons-lang3.jar" version="3.0.1"/>
<jar href="j2-org.springframework.asm.jar" version="3.0.5"/>
<jar href="j2-org.springframework.beans.jar" version="3.0.5"/>
<jar href="j2-org.springframework.context.jar" version="3.0.5"/>
<jar href="j2-org.springframework.core.jar" version="3.0.5"/>
<jar href="j2-commons-logging.jar" version="1.1.1"/>
<jar href="j2-basicplayer.jar" version="2.3"/>
<jar href="j2-jl.jar" version="1.0.1"/>
<jar href="j2-mp3spi.jar" version="1.9.4"/>
<jar href="j2-tritonus-share.jar" version="0.3.6"/>
<jar href="j2-xpp3-1.1.3.4d_b4_min.jar" version="1.1.3.4"/>
<property name="jnlp.versionEnabled" value="true"/>
<property name="sun.java2d.d3d" value="false"/>
</resources>
<application-desc name="ADOM II 0.3.1" main-class="de.adom.jade.JADE" width="300" height="300"/>
</jnlp> ]
at com.sun.javaws.security.JNLPSignedResourcesHelper.checkSignedResourcesHelper(Unknown Source)
at com.sun.javaws.security.JNLPSignedResourcesHelper.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.access$000(Unknown Source)
at com.sun.javaws.Main$1.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)