Issues with SMTP on Horde

Hi,<br /><br />    I am trying to use Horde to reply to an user that wrote to <a class="moz-txt-link-abbreviated"
href="mailto:it@postgresql.org">it@postgresql.org</a>,but when I try to send the message I get this error:<br /><br />
[SMTP:Invalid response code received from server (code: 554, response: 5.7.1 <wm.hub.org[200.46.204.128]>: Client
hostrejected: Access denied)]<br /><br />    Could you please advise?<br /><br /> Thanks,<br /> Gabriele<br /><pre
class="moz-signature"cols="72">-- Gabriele Bartolini - 2ndQuadrant ItaliaPostgreSQL Training, Services and Support<a
class="moz-txt-link-abbreviated"href="mailto:gabriele.bartolini@2ndQuadrant.it">gabriele.bartolini@2ndQuadrant.it</a> |
<aclass="moz-txt-link-abbreviated" href="http://www.2ndQuadrant.it">www.2ndQuadrant.it</a> 
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