Starting with OpenEdge Release 12.2.19, the ENCRYPT-AUDIT-MAC-KEY() method has been enhanced to accept an Encoding prefix as its second parameter.

ENCRYPT-AUDIT-MAC-KEY ( key, prefix )

If the prefix is omitted, invalid, or unsupported, the AVM raises a runtime error.

For more information, see ENCRYPT-AUDIT-MAC-KEY( ) method in the ABL Reference.