A short sample script

STEP One:

function __autoload($sClass) {
    echo $sClass."<br>";
}

ini_set(
    'unserialize_callback_func',
    '__autoload'
);

class myTestWithUpper {
    public $test;
    protected function __sleep() {
        return array('test');
    }
}

file_put_contents(
    "./test.dat",
    serialize(
        new myTestWithUpper()
    )
);

STEP Two:

unserialize(
    file_get_contents ("./test.dat")
);

Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to report
a bug at http://bugs.php.net/how-to-report.php

In php class names are not case sensitive and are stored in 
lowercase form internally. 

Ok, you say

> In php class names are not case sensitive and are 
> stored in lowercase form internally. 

but why does the __autoload() function not convert to 
lowercase if i make an instance like "new myTestWithUpper"?

this is a _little_ bit confusing :-(

Behavior is correct as you can see below:

marcus@zaphod /usr/src/php5 $ php -r 'class FOO{}$o=new FOO;var_dump(serialize($o));'
string(14) "O:3:"FOO":0:{}"

marcus@zaphod /usr/src/php5 $ php -r '$o=unserialize("O:3:\"FOO\":0:{}");var_dump($o);'
object(__PHP_Incomplete_Class)#1 (1) {
  ["__PHP_Incomplete_Class_Name"]=>
  string(3) "foo"
}

marcus@zaphod /usr/src/php5 $ php -r 'class FOO{}$o=unserialize("O:3:\"FOO\":0:{}");var_dump($o);'
object(FOO)#1 (0) {
}

Actually unserialized lowercases the classname. But we store the lowercased classname only in the hashtable while we preserver the casing for its real name.

This bug has been fixed in CVS.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.
 
Thank you for the report, and for helping us make PHP better.