Asterisk-IM not accessible

Via the Openfire Admin webinterface I have installed the Asterisk-IM plugin and an extra button on top has appeared, but I am unable to enter the settings for Asterisk-IM when I click the button…

It just loads forever !

What must I do to be able to enter the settings for this plugin ??

screenshot added…

This is the logfile :

2009.07.03 20:27:03 [org.jivesoftware.util.log.util.CommonsLogFactory$1.error(CommonsLogFactory.jav a:88)] Line=19 The content of element type “dwr” must match “(init?,allow?,signatures?)”.
2009.07.03 20:33:46 [org.jivesoftware.openfire.container.PluginManager.installPlugin(PluginManager. java:135)] Error installing plugin: Input stream was null or pluginFilename was null or had no length.
2009.07.03 20:33:46 [org.jivesoftware.openfire.admin.plugin_002dadmin_jsp._jspService(plugin_002dad min_jsp.java:170)] Plugin manager failed to install plugin: