pgsql: Document method of removing invalid UTF8 escape sequences from

Log Message:
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Document method of removing invalid UTF8 escape sequences from dump
file. Backpatch to 8.1.X.

Paul Lindner

Tags:
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REL8_1_STABLE

Modified Files:
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pgsql/doc/src/sgml:
release.sgml (r1.400.2.1 -> r1.400.2.2)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/release.sgml.diff?r1=1.400.2.1&r2=1.400.2.2)