I want to send MMS from a computer to my cellphone. How do I format text?

What markup language is used when sending MMS via em开发者_高级运维ail? I'm using PHP to send myself MMS via email from my server. But I don't know how to control layout and appearance. For example, I can't figure out how to make text bold, or change the color.

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MMS doesn't support special text formatting such as bold or italic!

Only the Enhanced Messaging Service (EMS) provides it. But in my opinion that's no good choice (see http://en.wikipedia.org/wiki/Enhanced_Messaging_Service) because the most devices to not support EMS.