Comment 4 for bug 359407

Using debug information from icedtea the problem appears to stem from "Error: create process":

  result = manager->CreateInstanceByContractID (NS_PROCESS_CONTRACTID,
                                                nsnull,
                                                NS_GET_IID (nsIProcess),
                                                getter_AddRefs (applet_viewer_process));
  PLUGIN_CHECK_RETURN ("create process", result);

which is called during initialisation:

ICEDTEAPLUGIN_DEBUG=1 firefox-3.5

...

Initializing JVM...
ICEDTEA PLUGIN: get component manager
ICEDTEA PLUGIN: liveconnect
ICEDTEA PLUGIN: thread manager
ICEDTEA PLUGIN: Instance::StartAppletviewer
ICEDTEA PLUGIN: get component manager
ICEDTEA PLUGIN: create local file
ICEDTEA PLUGIN: init with path
../IcedTeaPlugin.cc:3858: Error: create process
ICEDTEA PLUGIN: Instance::StartAppletviewer return
../IcedTeaPlugin.cc:1666: Error: started appletviewer
ICEDTEA PLUGIN: Factory::Initialize return