Check constraint question...

I'm trying to create a check constaraint and get error stating:

ORA-02436: date or system variable wrongly specified in CHECK constraint

Here is my constraint statement:
ALTER TABLE ACTIVITYTRACKING200205 ADD CONSTRAINT ACTIVITY200205 CHECK (ACTIVITYDATE BETWEEN '01-MAY-02' AND '31-MAY-02'); ACTIVITYDATE is defined as a DATE type. Don't understand why I'm getting the error. I'm using Oracle 9i

Thanks for any help

CJ Received on Wed Apr 24 2002 - 22:44:59 CDT