Log Message:
-----------
Fix CREATE TRIGGER release mention, WHERE -> WHEN.
Modified Files:
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pgsql/doc/src/sgml:
release-9.0.sgml (r2.25 -> r2.26)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/release-9.0.sgml?r1=2.25&r2=2.26)