The Email Archive tool/service can sometimes create records with null XML in the MAILARCHIVE_MESSAGE table.
This both currently causes problems in the tool (c/f
SAK-13480) and points to some other underlying problem (lost data?).
Our production db shows 76 records with null XML, as in:
select * from MAILARCHIVE_MESSAGE WHERE XML IS NULL order by MESSAGE_DATE;
dating back to 2007-05-24 and still being created in 2-5-x.