[Pljava-dev] Aborting a transaction

Hi,

I want to abort a transaction when a trigger on a table is fired.
Anyone knows how to do this? Is it something that can be done with
pl/java or rather at postgresql functions and procedures??

I read on the mailing list about a session manager and/or a
transaction listener:
- http://gborg.postgresql.org/pipermail/pljava-dev/2005/000148.html

and about changing the _new resultset value:
- http://gborg.postgresql.org/pipermail/pljava-dev/2005/000149.html

Basically a trigger is fired before an Insert and calls a function
that sends some data on a socket about the transaction. what i want to
do is abort the insert...

Any help?
Thanks for all your great answers...