temp table in pl/pgsql language

Good day.

 System Configuration
 ---------------------
   Architecture: Intel Pentium
   Operating System: FreeBSD 4.2-STABLE
   PostgreSQL version:   PostgreSQL-7.1RC1
   Compiler used:  gcc 2.95.2

 Description of problem
 ----------------------

It's may be postgreSQL limitation, but I found nothing information in TODO list
about this subject.

 If I use CREATE TEMP TABLE name(col1..) as SELECT query
in pl/pgsql functions - it's all OK. At the end of transaction server droped
this table automatically.
  But I can't use this possibility in TRIGGER's functions. Postgres take this
table as "permanent" (not temporary), I think. And on the second transaction
client received message as "ERROR, Relation name already exists". If I drope
this temp table in trigger's function, then error message like this: "ERROR:
Relation 32122 does not exist".


   Best regards..
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