Pad keeps jumping back to SIM unlock screen

[Shofar]

As I said recently I just (a few days ago) got the TPT and as I'm at a conference, not much time to really check things out.

Had to have it on full time for some hours yesterday and frequently (I can't figure out what does it), the TPT jumps back to the SIM unlock screen - I have a working 3 G model - apparently the European variety come with working 3 G.

Also when waking from sleep the first thing is the SIM unlock screen.

Is there anyway (besides taking out the SIM card) to stop the pad doing this?

wit thanks for the help.

Shofar
PS Cyberport in Berlin has them in stock - the Lenovo dealers from the web only have a demo and you have to wait for order. Cyberport also does Tax Free (actually it is 1/2 Tax free). No accessories though, not even a folio case. Pen included. So far very nice.