Currently Being ModeratedApr 25, 2013 2:47 PM (in response to MadnessUSMC)
When the iPhone sends mail, it uses the SMTP server that is associated with the email. The only time this doesn't happen is if there is a problem with that particular SMTP server and the phone will resort to the default SMTP server, which in your case appears to be the gmail one.
I suggest checking the work account and make sure it is working correctly and that the SMTP server is turned on. You can check what server it is using when you go into Settings>Mail, Contacts, Calendars. Open the work account, click on the SMTP listing and verify it is working.