I get the same error using junit 3.6 with jboss 2.4.1. on nt 4. Using the junit awtui causes the classcastexception when trying to narrow but the text interface works fine.
Just experienced this issue myself and found it documented in the FAQ that comes with JUnit 3.7...
You have to turn off the "Reload Classes every run" option in JUnit.
You can turn off JUnit's class reloading by setting "loading=false" in your junit.properties file, which is found by means of the USER.HOME system property.
For example, in your Ant build.xml file you can use something like:
another option is the -noloading flag when you start the gui client
I'm not sure if this is the same problem...but...
I use a WebStart client (WAR) that accesses a Session bean...I get the same Exception as above...This all worked under 2.4 but is causing me problems under 3.0.0
Is this the same problem?
What are you guys trying to do with these various flags?