Description:
------------
after calling str_replace on a nested array the resulting array changes values unexpectedly. Note that in the code below, there is no reference in the array values.

while trying different versions the code (reducing the size from my original code), the value of 
$fixed["firstlevel"] came also as :
&NULL
&UNKNOWN:0
bar
tostr
...
that may be related to Bug #23654?

regards,

Ivan

Reproduce code:
---------------
function foo ($someuselessvar,$str){
	$local=str_replace("fromstr","tostr",$str);
}
//----------------------------------------------/
function bar($var){
	$result=array();
	$result["firstlevel"]["secondlevel"]="$var";//unquote will change behavior!
	foo("someuselessstring", $result);
	return $result;
}
$first="foooo";
//$first="foooooooo";
$fixed=bar("$first");		//unquote will change behavior!
var_dump($fixed);
	
$tmp=bar("foo");
var_dump($fixed);
$tmp=bar("foooo");
var_dump($fixed);
$tmp=bar("foooooooo");
var_dump($fixed);
$tmp=bar("fooo");
var_dump($fixed);

Expected result:
----------------
Five times the same first dump!:
array(1) {
  ["firstlevel"]=>
  array(1) {
    ["secondlevel"]=>
    string(5) "foooo"
  }
}


Actual result:
--------------
array(1) {
  ["firstlevel"]=>
  array(1) {
    ["secondlevel"]=>
    string(5) "foooo"
  }
}
array(1) {
  ["firstlevel"]=>
  string(3) "foo"
}
array(1) {
  ["firstlevel"]=>
  string(17) "someuselessstring"
}
array(1) {
  ["firstlevel"]=>
  array(1) {
    ["firstlevel"]=>
    array(1) {
      ["secondlevel"]=>
      string(9) "foooooooo"
    }
  }
}
array(1) {
  ["firstlevel"]=>
  NULL
}