Log Message:
-----------
Add note warning against use of pre-8.4 multithreaded Tcl.
Modified Files:
--------------
pgsql/doc/src/sgml:
installation.sgml (r1.292 -> r1.293)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/installation.sgml?r1=1.292&r2=1.293)