Here is a new PHP class, that needs at least PHP5. 
This class implements Internet Printing Protocol on client side.

COPYRIGHT
    Copyright (C) 2005-2006, Thomas Harding.

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 
    51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

    thomas.harding@laposte.net
    Thomas Harding, 56 rue de la bourie rouge, 45000 FRANCE

HTTP BACKEND COPYRIGHT
    ./HTTP/http.php File is distributed under BSD License. See LICENSE file in
    ./HTTP.

STATUS
    Currently, it is able to print on an IPP server, parses server's response,
    is able to cancel jobs, and do all REQUIRED operations from RFC2911.


LIMITATIONS
    - There are known issues with authentication. currently, only "Basic"
      works, "Digest" fails systematically with CUPS server.
    - SSL/TLS will /probably/ work with strings, but as I don't hacked
      this part of http backed: printing files will surely fails.

DEPENDS
    It depends on "Class: http client" (slightly modified, shipped-with) and
    "class: SASL" (vanilla). See www.phpclasses.org.

DOCUMENTATION      
    Complete documentation is in "./documentation".

ORIGIN
    It is inspired by "PrintSendLPR", by Mick Sear, but there is no more code
    of it in. If you search for a very basic print client, uses it :)
    PrintSendLPR is available at http://www.phpclasses.org (license: LGPL).
    
TESTS
    Usage exemple is given in "TEST_PrintIPP.php".
    Test files are distributed under GPL.

Enjoy !
-- 
Thomas Harding.
