If it is not forced to be an object, we can not get to the cursor ID reliably on 32 bit platforms. Cursor IDs are 64 bit and we can not rely on people having the mongo.long_as_object turned on, or even mongo.native_long. The command cursor's result document is not something that is exposed, and all we really need is the cursor ID, so it's safe to force the return value to be a MongoInt64, which we then can reliable extract the object ID out of.