No wonder there is some misunderstanding. AMD made this very confusing because of their name scheme but here is what I figured out so far..
The original 754 socket Sempron was 32bit. Sometime around June or July AMD enabled the 64bit instructions and SSE3 then gave it the name Palermo. Look for the letters BX on the end of the processors OPN number. There could be other number/letter methods but that's all I've found so far.
I guess AMD is making these processors to compete with the 64bit Celerons.
- I should have added;
The socket A Sempron line starts at 2200+ / 1500mhz., 128/256 cache
The socket 754 Sempron line starts at 2500+ / 1400mhz., 128/256 cache
You are correct, the 2200 Sempron isn't 64 bit enabled. Good catch