Creating watermark with transparency on jpeg using PIL?

[tvmaly at gmail.com]

I have been trying to add a watermark to a jpeg using PIL, but the
watermark has a black box around it.  I looked at

http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/362879

and

http://mail.python.org/pipermail/python-list/1999-May/003369.html

but I think these only refer to gif or png.  I know jpegs really do not
support transparency, but is there some way to take a watermark in a
non jpeg format and add it to a jpeg without that box appearing around
it?

        Best Regards

                   Ty