The zabbix server sometimes dies with these messages:

Query::select new.itemid from items new, items dest where dest.itemid=10420 and new.key_=dest.key_ and new.hostid=10020
Query failed:PGRES_FATAL_ERROR:FEHLER: NEW in einer Anfrage verwendet, die nicht Teil einer Regel ist
(in english: NEW used in a query that is not part of a rule)

Obviously the query uses new as aliasname, which causes a conflict with the predefined NEW variable.

In the source, I find this problem in two files:
frontends/php/include/graphs.inc.php on line 209
src/libs/zbxdbhigh/host.c on line 973

I replaced the token 'new' by 'neww' in these two queries, then my problem disappeared.