Alfresco how to send email to other domain

I have configured the alfresco email outbound like this

 mail.host=mailserver.com
 mail.port=25
 mail.username=uname
 mail.password=pword

now I can send mail to email address like abc@mailserver.com but abc@otherdomain.com. how to send email to other domai? thanks!!!(my alfresco edition is community 4.2.x)

Solution

Promoting a comment to an answer...

Alfresco itself has absolutely no problems with sending emails to any destination domain

However, when you setup outbound SMTP for Alfresco, you specify a mail server to use for handling outbound messages. That server needs to be configured to allow mail relaying from the Alfresco host. If it isn't, then you'll often see that internal emails are fine, but external emails are rejected. Make sure your mail server is configured to allow Alfresco to send (relay) emails through it, and you'll be fine!