Check the release notes or changelogs..
I believe there was a notable change in 4.0.5 regarding 'referencing' you may have to deal with, and 'reference counting' was added later on but this should have little affect on backwards compatibility. Also, the input mechanism has changed, although you could get the old behaviour back by changing the php.ini , it is recommended for a number of reasons to 'upgrade' your source to ensure it will continue to work in future versions of PHP. See: http://www.php.net/release_4_1_0.php HTH, bvr. Aras Kucinskas wrote: >I want to upgrade PHP from 4.0.4 to 4.1.2. >Where I can find docs apbout version differences. > -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php