All x61 Tablets have SIM card slot build in?

[bin.dong]

I installed 2GB Ram for my X61 T today and found out... ...I do have that SIM card slot!! It's just under Ram slot. I checked device manager, no such device found. I didn't try my SIM card on it yet, but I am wondering if it's gonna work without any applications to support it?

My tablet looks like all other regular Lenovo tablets without mobile board. I mean why I don't have that additional antenna on top of the LCD screen?

[bin.dong]

No one knows why I have that SIM card slot? Anyway, I tried my SIM card on it, won't work at all.

[alexperez]

The X61 has two mini pci-e slots under keyboard, when you buy your thinkpad from lenovo you can customize it adding or not including cards like: wireless, intel turbo memory or WWAN. These three types of cards are installed on mini pci-e slots so you can only have two installed at the same time.

You can add cards by yourself after purchasing (it may require additional antenna installation for abgn or wwan wireless).

The SIM slot available but not working allows you to upgrade your thinkpad with WWAN on future.