My portlet plugin does not have a thumbnail (I don't think Jira would find it inside my plugin jar, so I don't know where to put it).

When I deploy the plugin I get the following exception:

2004-10-11 11:22:33,395 ERROR [com.atlassian.jira.ComponentManager] Error occurred while starting component.
java.lang.NullPointerException
at com.atlassian.jira.plugin.portlet.PortletModuleDescriptor.init(PortletModuleDescriptor.ja
va:56)
at com.atlassian.plugin.loaders.SinglePluginLoader.createModuleDescriptor(SinglePluginLoader
.java:160)

I guess line 56 in PortletModuleDescriptor
thumbnail = element.element("thumbnail").getTextTrim();
is a bit optimistic