[Koha] Saving a new item type

[Paul A]

I'm looking for some help please having come up against a brick wall.

We defined a new "Item Type" "Files and Binders" code 'FB', made a new 
Framework structure, and entered a few biblios/items to verify it. Appears 
to work, see 
<http://opac.navalmarinearchive.com/cgi-bin/koha/opac-MARCdetail.pl?biblionumber=25936> 
where both the 942$c and 952$y are _correctly_ showing 'Files and Binders'

However, we use a script that needs $itemtype and which works perfectly for 
all item types _except_ this new one. So I looked into the MySQL side of 
things, and the new 'FB' is _not_ getting saved:

mysql> SELECT itemtype from biblioitems Group by itemtype;
+----------+
| itemtype |
+----------+
| NULL     |
| AU       |
| BK       |
| CM       |
| CR       |
| HB       |
| VI       |
| VM       |
+----------+
8 rows in set (0.00 sec)

and

mysql> SELECT 
ExtractValue(marcxml,'//datafield[@tag="952"]/subfield[@code>="y"]') AS 
itemt FROM biblioitems HAVING itemt REGEXP 'FB';
Empty set (0.59 sec)

"Test MARC biblioframework" is good. All other cataloguing is fine.

I must be doing something wrong or making a basic mistake that I just can't 
see.

Help or suggestions on adding a new "itemtype" would be warmly welcomed.

Thanks -- Paul