[xwiki-users] Registration through mail

Hi, trying to use the registration through e-mail, when registering I get this error: Error number 10003 in 10: Exception while sending email from [email protected] to [Ljava.lang.String;@6bf4fe Wrapped Exception: Connection refused I put the right information in the preferences, IP of the mail server and email for the admin on that server. Did anyone experienced the same problem? Vito