OK - as long as you think it's safe.... I seem to recall headlines about someone doing that, and it wasn't good news!
We are missing one of the kittens (well ok, she not really a kitten any more, but you know what I mean). Shebob is a roamer...loves to go out "hunting". She left 3 nights ago and we haven't seen her since. Brindle on the other hand, hangs out down by the house all the time. I know you've had cats gone for long periods of time, but I don't have a good feeling about it. Thegirl is sad...I had a dream last night that she came back and brought 6 of her cat friends. :-)
Mrsnad