In PHP 5.2 the toString() method is used to convert an object to a string. In PHP 5.1 the toString() method is used to convert an object to a string but only when print or echo is called on the object. So, doing something like this won't work in 5.1:

foo = bar($object." won't convert object to string");

I'm trying to build PHP against the MySQL supplied binary on my Mac mini running 10.4.9. For some reason it's looking in the wrong place for libraries, so I get the following error:

/usr/local/mysql/lib/mysql/libmysqlclient.15.dylib Referenced from: /Users/michael/build/php-5.2.3/sapi/cli/php Reason: image not found

/usr/local/mysql/lib exists and contains the libraries. It seems like a horrible fix but the following "fixes" the problem:

sudo ln -s /usr/local/mysql/lib /usr/local/mysql/lib/mysql

When you save an object to a session in one file, say write.php, and then retrieve it from another, say read.php, PHP needs to know about the class definition so that it knows how to unserialize it from the session. If you don't include the class in read.php, you'll get an error complaining about __PHPIncompleteClass.