Charlie Chaplin and the Cell Phone: Explanations

It's a big deal on the net right now that a filmmaker seems to have found a woman talking on a cell phone back in 1928 in the features section of a Chaplin film.  Here are a few problems:

1.  If you come from far enough in the future to time travel, you probably aren't carrying a phone about the size of a Motorola Razr.
2.  Whoever put the DVD together could have inserted this person.
3.  Okay, you have a cell phone, where are the towers you need to get a signal?
4.  Okay, you have a cell phone, who are you talking to on the cell phone?
5.  My suggestion is that she's holding something black against her face.  A cold compress for pain in the jaw or ear, perhaps?