[Koha] Koha/Zebra record lengths

[Paul A]

We've lost a record (opac and staff) biblio + 422 items. It's there in 
all its glory in MySQL, but Zebra won't show it. The Koha wiki mentions:

"Record length of 101459 is larger than the MARC spec allows (99999 
bytes) -- This will show up if you are trying to index a record that has 
a large number of items (common with serials, for example), or just has 
a lot of text in the record itself. /.../ Koha can do the indexing by 
using the MARCXML format rather than ISO 2709, and this gets around the 
problem. If you add '-x' to the reindex_zebra.pl command when indexing 
biblios, it will do this"

We always have used '-x' for biblios (did it again a couple of minutes 
ago.) No joy

I can (I hope!) just delete the last item (or two or three) from MySQL 
and reindex, but before I go there, does anyone have previous experience 
with this problem?

Many thanks --Paul