Setting Transaction level doesn't work - Mailing list pgsql-admin

Hi all,

I've tried to set the transaction isolation level in 6.5 to serializable

with "set transaction isolation level serializable" in psql. A "show
transaction isolation level" tells me that it is still "read commited".
Any Hints ?

Is there a possibility to have transaction level setted to serializable
as default level?

Many thanks in advance

Norbert