Not sure how you managed that Sith_Apprentice. MMS is reliant upon WAP MMS Transport/MMS client service books, which are delivered by the relay. The only way you can connect to the relay is via the APN provisioned by your carrier for BlackBerry use.
The settings herein relate to a service provided by your carrier however, and so would work if this Service book was in the device even if you weren't subscribed to BIS/blackberry APN. The same is also true of the browser, provided the Service book for the browser in use has the settings in for either WAP or internet use via your own carrier's APN.