How to force the Android Mobile keyboard to numbers?

Question

Specifically, how do I get it to pop up as the numbers entry screen but still be able to switch to letters? What I'd really like, ideally, is to have it act the same as if we had the xml property

<EditText
    ...
    android:inputType="textShortMessage"/>

but come up on the number entry screen (the one you get by clicking "?123") on first showing, rather than the usual qwerty one. I've tried doing eg

<EditText
    ...
    android:inputType="textShortMessage|number"/>

but all that does is default it to the phone-number-entry screen with no option to enter letters. Any ideas?