Default Imei Question on Android Tablet

I am currently working on a rooted tablet that has no phone built in. How do you find out what the imei value is currently set to? I have a suspicion that it is completely absent as I cannot get the market to work and slideme.org said that it does not register a "deviceID (eimi)"

I have seen the posts about the legality of the iemi on phones but how about when I am trying to get it working on a non phone.

Thanks in advance.