Unable to identify an ordering operator '<' for type 'xid'

I'm getting this error showing up in my server log:

    ERROR:  Unable to identify an ordering operator '<' for type 'xid'
        Use an explicit ordering operator or modify the query

This is after I have enabled Row Versioning in the ODBC Driver.  I did some
searching but I have yet to find any information except for an old thread
(http://archives.postgresql.org/pgsql-interfaces/2000-09/msg00022.php).

Any help would be appreciated.  I figure I need to create the < operator,
but I don't know what the proper syntax for creating this would be, or what
type of function it would require to work properly.  Also this is using ODBC
from MS Access if that matters at all.

Rob