jdbc connection - UnknownHostException

Hello list,
Can anyone help me with this issue?
I'm trying to write a bean (used within the struts framwork) that gives some methods about managing the database, located on http://myhost1.org. After some attempts, the connection succeded, but when a tried it again, I received an UnknownHostException. I've then tried after many things to connect through the db with another alias, http://myhost2.org (which is the very same ip than myhost1.org) and it works a few times.

I've then written a small test class, which looks very like what is in the bean, to connect on a postgresql:

Class.forName("org.postgresql.Driver"); //load the driver
db=DriverManager.getConnection("jdbc:postgresql://myhost1.org:5432/dbname", "user", "pwd");
//...
db.close();

and it works fine, no exceptions (loading driver and connecting ok).
But in the same time, the connection in the bean does not succeed any more...

The driver is always correctly loaded.
What am I missing? thanks for any answer :)
yann

--
Yann Calderara <cy(at)netlabs(dot)org>
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