[Koha] Zebra index problem after upgrade to 3.18

[clint.deckard]

I upgraded a 3.10 package installation on Debian squeeze to 3.18.03 and 
now zebra will not reindex.
Behaviour was exactly like Bug 13396/13404
	
I looked to change to DOM indexing but the wiki instructions were unclear.
I added
<zebra_bib_index_mode>grs1</zebra_bib_index_mode>
to the koha.conf file but no progress.
Could someone kindly suggest a next step please.

Thank you,
Clint.


koha-rebuild-zebra -f -v gives:

Zebra configuration information
================================
Zebra biblio directory      = /var/lib/koha/koha/biblios
Zebra authorities directory = /var/lib/koha/koha/authorities
Koha directory              = /usr/share/koha/intranet/cgi-bin
Lockfile                    = /var/lock/zebra_koha_koha/rebuild/rebuild..LCK
BIBLIONUMBER in :     999$c
BIBLIOITEMNUMBER in : 999$d
================================
skipping authorities
====================
exporting biblio
====================
1............................................................................... 
 
101............................................................................. 


etc
 
5001............................................................................ 
                          5101..............................................
Records exported: 5147
====================
REINDEXING zebra
====================
07:46:54-16/02 zebraidx(11623) [warn] 60:0:XML error: junk after 
document elemen                          t
07:46:54-16/02 zebraidx(11623) [warn] 1:0:XML error: not well-formed 
(invalid to                          ken)
====================
CLEANING
====================
Zebra configuration information
================================
Zebra biblio directory      = /var/lib/koha/koha/biblios
Zebra authorities directory = /var/lib/koha/koha/authorities
Koha directory              = /usr/share/koha/intranet/cgi-bin
Lockfile                    = /var/lock/zebra_koha_koha/rebuild/rebuild..LCK
BIBLIONUMBER in :     999$c
BIBLIOITEMNUMBER in : 999$d
================================
====================
exporting authority
====================

Records exported: 0
====================
REINDEXING zebra
====================
skipping biblios
====================
CLEANING
====================