I've got a fairly simple, bog-standard PHP emailer script that's posted to from an HTML form. IE7 and Safari (for Win) has no issues with the script (i.e. instant transmission of message) but there seems to be a delay when done through Firefox. I thought it may have been the server but several test messages sent through the other browsers worked fine in the time between the FF send and the Outlook receipt.
I will check this some more tonight, but has anyone encountered this before?