problem with 3.0.1 beta, "processing check-types agenda"

 Hi,

I am running under cmucl: CMU Common Lisp CVS Head 2003-09-14 16:41:12.
I seem to be able to get through all of the powerloom-run-test tests... pretty 
much. However, the following kicks me out of powerloom without a chance to 
look at the stack:

(powerloom)
    Welcome to PowerLoom 3.0.1.beta

Copyright (C) USC Information Sciences Institute, 1997-2003.
PowerLoom is a trademark of the University of Southern California.
PowerLoom comes with ABSOLUTELY NO WARRANTY!
Type `(copyright)' for detailed copyright information.
Type `(help)' for a list of available commands.
Type `(demo)' for a list of example applications.
Type `bye', `exit', `halt', `quit', or `stop', to exit.


|= (defconcept Primary-Color (?c)
     :<<=>> (member-of ?c (setof Red Green Blue)))

|c|PRIMARY-COLOR

|= (defconcept Snark (?x))

|c|SNARK

|= (defrelation Boojum ((?x Snark) (?y Primary-Color)))

|r|BOOJUM

|= (assert (Snark Fred)) 

|P|(SNARK FRED)

|= (assert (Boojum Fred Olive-Drab))

|P|(BOOJUM FRED OLIVE-DRAB)

|= (retrieve all (?x) (Primary-Color ?x))

Processing check-types agenda...
; Caught native non-STELLA exception #<TYPE-ERROR {488DB315}> at top level.
0: (DEBUG:BACKTRACE 536870911 #<Synonym Stream to SYSTEM:*STDERR*>)
1: (STELLA::%%PRINT-EXCEPTION-CONTEXT #<unavailable-arg> #<unavailable-arg>)
2: (STELLA::PRINT-EXCEPTION-CONTEXT #<unavailable-arg> #<unavailable-arg>)
3: (STELLA::POWERLOOM)
4: (INTERACTIVE-EVAL (POWERLOOM))
5: (LISP::%TOP-LEVEL)
6: ((LABELS LISP::RESTART-LISP
      SAVE-LISP))
Exiting PowerLoom.

NIL
* 
-- 
Best Regards, 
- Peter 

Peter Denno 
National Institute of Standards and Technology, 
Manufacturing System Integration Division, 
100 Bureau Drive, Mail Stop 8264             Tel: +1 301-975-3595 
Gaithersburg, MD, USA 20899-8264          FAX: +1 301-975-4694