How can I get the status tracking to work on GW8 when sending to Internet email addresses?

I know it works inside of the company, but when we send it out, all it shows - "transferred". I know at least 2 other companies that we have emailed to are using Groupwise... I understand that not all the system may support this feature but... we do not get tracking for any of the internet emails.

I tried under the client Tools->Options->Send, mail tab, internet mail delivery confirmation and send notification to my mailbox.... it is enabled.

What am I doing wrong?
Thanks in advance