I've just tested with latest php 5 (php5-200503080930)
and the problem is not solved.

At the moment __call() relies on the internal signature which is return by copy and the fact that the engine prevents from implementing return by reference functions at c-level.

well, then that info about __call and return by reference should go into the manual, in the __call section.
right?

Andi, is this the final call? :)
(documentation or engine change..that is the question)

PHP Strict Standards:  Only variables should be assigned by reference

With all due respect, "only variables should be assigned by reference" makes no sense.

__call does not assign variables.  It executes code for innaccessible methods, and that code may wish to return a reference.

Not bogus; this functionality existed in PHP4 as __call()'s third parameter was passed by reference.

Although this is in no way justification for the fix (as I have already justified it) consider this: (pedantic error checking removed for simplicity)

<?
class Foo
{
    private $world;

    function &__call($method,$params)
    {
        if( substr(0,3,$method) == 'get' )
            return $this->{substr($method,3)};
    }

    function &__get($property)
    {
        return $this->{'get'.$property}();
    }
}

$hello = new Hello;
$hello->world[] = 'php maintainers always say NO';
?>

--which does not work.  For those of us mere 'users' who need this, as a work around try this:

<?
class Hello
{
    . . . include definition from above . . .    

    function &getWorld()
    {
        return $this->world;
    }
}
?>

--which DOES work, although that is not really the point!