Only Microsoft could do that:
“This article provides information to help you understand how Windows Phone 7 devices use SD cards, the performance requirements of SD cards for Windows Phone 7 devices, and how your phone will behave if you remove the SD card or add a new one.
Some Windows Phone 7 devices include a Secure Digital (SD) card slot underneath the battery cover. If you buy a Windows Phone 7 device that includes an SD card slot, you should be aware of several important differences from other devices that use SD cards:
The SD card slot in your phone is intended to be used only by the Original Equipment Manufacturer (OEM) that built your phone and your Mobile Operator (MO). These partners can add an SD card to this slot to expand the amount of storage on your phone.
To help ensure a great user experience, Microsoft has performed exhaustive testing to determine which SD cards perform well with Windows Phone 7 devices. Microsoft has worked closely with OEMs and MOs to ensure that they only add these cards to Windows Phone 7 devices.
You should not remove the SD card in your phone or add a new one because your Windows Phone 7 device might not work properly. Existing data on the phone will be lost, and the SD card in your phone can’t be used in other Windows Phones, PCs, or other devices.”
From http://support.microsoft.com/kb/2450831 (and the madness goes on in that article…)