Thanks for the reply but I'm still stuck. Nearest I can find on Eclipse 3.1.0 is Window>Preferences>Java>Installed JREs but that already points to JDK1.5 Eclipse is running that happily it is just when I tryto start JBoss via Default Server>Start (or the equivalent icon) that I get the error message. If I run the same installation of JBoss through a cmd window it picks up JDK1.5 as well. System variables also have JAVA_HOME pointing to jdk1.5 Is there a specific config file that the JBoss-IDE uses to start JBoss that I'm overlooking? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3963040#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...