Just a tip for those setting up cups to let windows clients print via
IPP....

Remove any commas from the nickname line in /etc/cups/cupsd.conf.  There's a
bug in windows where it doesn't like the commas.  And don't use ipp:// when
setting up windows clients, you have to use a URL of the form
"http://myhost:631/printers/myprintername"

Spent like 2 hours troubleshooting this, and finally found the answer to the
comma problem on a page written in swedish.  :)

Note that you'll need to put "AuthType None" under the location sections for
"/" and "/printers" since it appears that windows doesn't like
authentication over IPP.

Jay