Some useful links on SDO:
1. Quick intro ( http://www.obalweb.net/wppro/?p=19 )
2. SDO for Zend Conf 2005 ( http://www.ibm.com/developerworks/forums/weblogs/data/SDOforZendConf2005.pdf ), Presentation, [481 KB], Graham Charters, 2005-10-18
3. Introducing Service Data Objects for PHP ( http://www.zend.com/pecl/tutorials/sdo.php ), 2005-08-05
4. Service Data Objects specification ( http://www.ibm.com/developerworks/library/specification/j-commonj-sdowmt/ ), 2003-2005
HTH,
R. Rajesh Jeba Anbiah