Hi, I am trying to register Java exceptions using REGISTER-JAVA-EXCEPTION but it does not seem to work for me as evidenced by the transcript below. Is there anything that I may have missed? Armed Bear Common Lisp 0.23.1 Java 1.6.0_20 Sun Microsystems Inc. Java HotSpot(TM) 64-Bit Server VM Low-level initialization completed in 0.354 seconds. Startup completed in 1.579 seconds. Type ":help" for a list of available commands. CL-USER(1): (define-condition java-illegal-argument-error (java-exception) ()) JAVA-ILLEGAL-ARGUMENT-ERROR CL-USER(2): (register-java-exception "java.lang.IllegalArgumentException" 'java-illegal-argument-error) NIL CL-USER(3): (ignore-errors (jstatic (jmethod "java.lang.String" "valueOf" "int") "java.lang.String" "12")) NIL #<JAVA-EXCEPTION {4A6F19D5}> CL-USER(4): (jstatic (jmethod "java.lang.String" "valueOf" "int") "java.lang.String" "12") #<THREAD "interpreter" {2690ED81}>: Debugger invoked on condition of type JAVA-EXCEPTION #<JAVA-EXCEPTION {74D8C3EE}> Restarts: 0: TOP-LEVEL Return to top level. [1] CL-USER(5): 0 CL-USER(6): Kind regards, Martin.