Sempron: 64-bit CPU?

Related to the last thread, but moving away from the MB focus to the CPU:

The product specs on this eMachines T3104 (at
http://www.emachines.com/products/products.html?prod=eMachines_T3104)
apparently has a 64-bit Sempron CPU. Specifically, "AMD Sempron 3100+
Processor (64-bit)" is how it is stated.

I have concerns as to whether this is truly a 64-bit CPU. AMD's website
seems to differentiate their CPU product line as "AMD Athlon 64" and "AMD
Sempron". I have not found a single reference on AMD's website that mentions
any Semprons sporting a 64-bit CPU. Their Athlon64 pages all have splashy
"ready for 64-bit OS" type stuff on them.

The spec sheet (http://www.fic.com.tw/product/motherboard/amd/k8m-800m.aspx)
for the MB that is installed on the eMachines T3104, an FIC K8M-800M, shows
"Athlon 64 clawhammer (K8) up to 3600+" for the processor. If that's the
case, could you even put a 32-bit processor on this MB if you really wanted
to?

Tried to get eMachines support to tell me the AMD part number for the
Sempron on the T3104, but they didn't have that information (Surprise!
Not!). They suggested I call their parts depot, and I did, but got
disconnected after being on hold for 15 minutes. The old Gateway still
hasn't changed their ways.

Anybody know of references that can definitively identify whether this CPU
is truly 64-bit?

TIA,
Dan