As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT FL220 THE RT ENG LOW OIL PRESS MESSAGE APPEARED ON THE EOAP. OIL PRESS WAS AT 33 PSI AND OIL QTY WAS AT ZERO. SHUTDOWN ENG AND DIVERTED TO IAD DUE TO CROSS WINDS AT DCA AND LONGER RUNWAY AT IAD. CONTRACT MAINTENANCE FOUND THE NR 2 ENG OIL FILTER CAP O-RING WAS CUT. REPLACED O-RING AND C/W M/M INSP REQ FOR WINDMILLING.