pg_sorttemp files

I have tons of old files with names like base/db/pg_sorttemp####.##.  Iassume that they are temporary sorting files but
somehowthey never got
 
cleared out.  Is it safe to delete these from a running system.  The files
are months old.

-- 
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
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