Why my Ipad 4g lag at start up?

I bought a New Ipad 32 Gb with Cellular last week. I am not using cellular for now. So I did not insert a sim card. I updated to ios6 at first use but I really dont remember if it was lagging on that time. The problem is, my ipad is lagging at start up for almost 5 seconds. It is looking for a sim card at start up and the ipad is lagging while its looking for sim card. After the 'sim card not found' dialog appeares its starting to work! Sometimes its lagging when Im shifting the main pages. But the start up lagging is worse.

So is there anybody have an idea about this problem? How can I fix this? Can I fix if I find a way to stop look for sim at start up?