For IllegalComponentStateException thrown from java.awt.Component is needed better description, i.e. the most desired is to dump the actual instance of the Component throwing the exception.
This is needed for better identifying of the problem in big application, in our case Netbeans (see Issuezilla #12541 and related bugs), which is now almost impossible with current exception message description.

I guess there should be a rule the exception (runtime especially) should always provide as much available info as possible.