I'm throwing this one open to the floor. Does anyone have any suggestions that might help? Here is the situation - I have a laptop and a desktop with seemingly identical software setups. Both are running W2K, Eclipse 2.1, Tomcat 4.1, Sysdeo TomcatPlugin 2.1 and are running the identical Struts project out of the same source repository. On the laptop, everything is fine. Hitting the Tomcat start button in Eclipse fires it up and everything runs just fine. On the desktop, hitting the Tomcat button almost immediately causes a fatal halt with a NoClassDefFoundError on the class javax.management.MBeanRegistration. On the desktop, Tomcat will start just fine if you start if from the startup.bat file but not from within Eclipse.

I have set the two computers side by side and walked through every option I can think of in Eclipse, in the Tomcat plugin settings, in the Tomcat config, in the environment variables. Both computers can run the StrutsUnit test cases successfuly. It is obviously classpath related on the Tomcat startup, but I can't figure out why this is a problem. On the desktop. the TOMCAT_HOME option in the Sysdeo config is set to the correct directory, and I can open the jars by hand and see that in TOMCAT_HOME/server/lib is the jar mx4-jmx.jar, which contains that class. What I cannot figure out is why the desktop cannot find the class. My guess is that there is a very small delta between what I have and what would work fine, but I can't find it. The only reference google turns up for a similar problem is a guy trying to use a launcher from within IntelliJ. If you can help, please leave me a comment so that conceivably this can help the next person to google it.

UPDATE - I've now installed this same setup on a third Windows 2000 machine, and the third one worked fine. I'm suspecting that maybe I have a bad Tomcat installation on the machine that isn't working. I think I'll give it a shot, uninstalling and reinstalling.

FURTHER UPDATE - The problem is solved by a generous passerby named Brian. Look in the writebacks, his suggestion cleared my problem right up. Thank you Brian!