Performance problem on delete from for 10k rows. May takes 20 minutes through JDBC interface

Hi all,

Il get this strange problem when deleting rows from a Java program.
Sometime (For what I noticed it's not all the time) the server take
almost forever to delete rows from table.

Here It takes 20 minutes to delete the IC table.

Java logs:
INFO [Thread-386] (Dao.java:227) 2005-03-15 15:38:34,754 : Execution
SQL file: resources/ukConfiguration/reset_application.sql
DELETE FROM YR
INFO [Thread-386] (Dao.java:227) 2005-03-15 15:38:34,964 : Execution
SQL file: resources/inventory/item/reset_application.sql
DELETE FROM IC
INFO [Thread-386] (Dao.java:227) 2005-03-15 15:58:45,072 : Execution
SQL file: resources/ukResource/reset_application.sql
DELETE FROM RA

I get this problem on my dev (Windows/7.4/Cygwin) environment. But now
I see that it's also have this problem on my production env. Yes I
tought I was maybe just a cygwin/Windows problem .. apparently not :-((((

On my dev I can see the Postgresql related process running at almost 50%
of CPU usage for all the time. So I suppose it's something inside
Postgresql. I rememeber having tried to delete the content of my table
(IC) from PgAdminIII and I took couples of seconds!!! Not minutes. So
the process don't jam but take time .. any Idea what postgresql is doing
during this time??

If you have any idea on what the problem could be... I really appreciate
it.

Thanks for any help!
/David