Question : Cannot send from exchange 2007

I am setting up exchange 2007 server for the first time.  I have set up exchange server 2003 many times but this is really different.  
The exchange has 2 nics, local network (192.168.1.11) and one to a MailScan (192.168.3.2) for spam and virus protection.
The MailScan box has 2 nics one to the exchange box (192.168.3.1) and one to the firewall (192.168.4.2).

I can receive email
I cannot send email

I created a hub transport to the Internet,
Put my FQFN mail.domain.com,
Address space * type SMTP
Route mail through smarthost  192.168.3.1
Source server is this single exchange server role is mailbox, client access, hub transport
Any ideas?

Answer : Cannot send from exchange 2007

Did you try the telnet tests ?
ID:26310570