Exclamation Point Next to Jars in Java EE Module Dependencies

I have a J2EE application that consists of an EAR and a WAR. The EAR contains all of the references to the external jars which I the开发者_JAVA技巧n reference on the Java EE Module Dependencies screen within Eclipse for the WAR. For certain jars I get an exclamation point next to the jar icon and do not understand why. I know for certain that those jars do exist and are in the location specified on the class path. Does anyone know why some jars exhibit this behavior? I know that I had a similar problem with Javassist and I was able to resolve it by rebuilding the source from scratch. Could this be caused by the code be instrumented?

The new jars that I'm having trouble with are jxl.jar and mvel2.jar which I got out of the jboss drools distribution.

Thank you very much for your assistance, Jeremy

I've had red exclamation points before that were a symptom of subversion errors caused by copying a folder on the filesystem and inadvertently copying the invisible .svn directory. If the exclamation point is red, then you may have the same problem.

To fix it, I found the .svn directory in the folder (it was something like /projectName/src/main/java/com/package/name/.svn) then deleted it and performed an update followed by a commit and it was all back to normal.