2.3.5.1 and debug mode

i recently upgraded to jde 2.3.5.1 and now my source code window
in debug mode no longer works. the backtrace error is:

Debugger entered--Lisp error: (wrong-type-argument stringp nil)
  string-match("[$]" nil 0)
  split-string(nil "[$]")
  jde-remove-inner-class(nil)
  jde-find-class-source-file("com.m2g.score.task.ScoreCommandImpl")
  jde-db-find-class-source("com.m2g.score.task.ScoreCommandImpl")
  jde-db-set-debug-cursor("com.m2g.score.task.ScoreCommandImpl" "ScoreCommandImpl.java" 56)

i'm running FC4 with gnu emacs 21.4.1, is this an emacs version
incompatibility? anyone recommend a patch to emacs or jde?