[SQL] temp table existence

[Marcin Krawczyk]

Hi all. Is there a way to determine the existence of a TEMP
TABLE? I need to check i it exists before I create it. Doing simple
check on pg_class or pg_tables is
not enough because there may be other such tables created in other sessions.
Or maybe anyone knows the identification (apart from 'others') of error to
trap it with EXCEPTION clause?