SMTPSend problems on Mac

[Bob Fiering]

Hi,

I have a customer with strange problems when trying to send mail in Omnis 5.2.3 on OSX.
When entering the credentials for their account i got errors like
-1034 Connection time out. Sometimes even -10060 Socket error: Connection timed out

When entering gmail smtp settings settings smtp.gmail.com <http://smtp.gmail.com/> with the user authentication settings, verify true and SSL true, everything is running fine.
But their own mail account (running at a web/mail server provider) gives problems.
I tried to add portnumbers like 587 or 465 to their smtp server address but no luck.
The same error -1034. 

Anyone any idea.
I tried to use for their email account the gmail smtp server but then their own email addess is replaced by the gmail address from the authentication when a customer gets the mail.

Anyone an idea what is happening here and how to solve it?

Thanks,

Bob