just read here what some other guy posted:

The fix for this has to be done by T-Mobile engineers. The problem, as mentioned earlier, is that many end-user devices using T-Mobile network are not configured (or not properly configured) in the T-Mobile's MMS (multi-media messaging service, also known as 'picture messaging') configuration. Typically, as a fail-safe mechanism, an MMS node will default the message to a 'safe' message when a device is unknown, or not completely configured. This may mean that some unknown devices may be treated as not being capable of receiving an MMS message (aka 'picture message') and will receive only a text message with a link to a web; others may be assumed as being capable of MMS but lacking sufficient capabilities to get the content with larger pictures or to receive larger messages, so the fail-safe mechanism in the operator's MMS service kicks in and transforms the original message to something smaller. The problem here is that T-Mobile consistently refuses to properly configure certain phones, including Nokia N8, N97, N5800, in their MMS solution - because these phones are 'not supported by T-Mobile'. This is hurting T-Mobile users who decide to use a phone approved for USA networks, but not on the list of T-Mobile supported phones. The fix is not hard, it is a matter of changing or adding few parameters. The mechanism already exists, and I am sure that T-Mobile in US has the exact configuration that the folks in US can use. So this is simply a question of T-Mobile's interest to actually assist its users. While I can understand that not every new device can be immediately configured, It is a shame they still refuse to do so for the devices that are in use for quite some time, such as Nokia N8, N97, N5800. As a T-Mobile US customer I’ve called their tech support twice during the last year and explained what needs t be done and asked them to pass the message to the network engineers… it’s been several months since my last call, and no change. If anyone from the T-Mobile management is reading this, please take some action; your engineers can do this in less than 8 hours of work (the fix takes less than 30 mins, the others 7.5 hours are for testing). Please.

Plz, call technical support, ask for supervisor and tell him this story. That's only the way to help us.