<p>Below is an example class hierarchy and code. What I'm looking for is a way to determine if 'ChildClass1' or 'ChildClass2' had the static method whoAmI() called on it without re-implementing it in each child class.</p>

<pre><code>&lt;?php

abstract class ParentClass {

    public static function whoAmI () {

        // NOT correct, always gives 'ParentClass'
        $class = __CLASS__;

        // NOT correct, always gives 'ParentClass'. 
        // Also very round-about and likely slow.
        $trace = debug_backtrace();
        $class = $trace[0]['class'];

        return $class;
    }
}

class ChildClass1 extends ParentClass {

}

class ChildClass2 extends ParentClass {

}

// Shows 'ParentClass'
// Want to show 'ChildClass1'
print ChildClass1::whoAmI(); 
print "\n";

// Shows 'ParentClass'
// Want to show 'ChildClass2'
print ChildClass2::whoAmI();
print "\n";
</code></pre>

I believe what you're referring to is a known php bug. Php 5.3 is aiming to address this issue with a new Late Static Binding feature.
http://www.colder.ch/news/08-24-2007/28/late-static-bindings-expl.html