Description:
------------
I was using one simple preg_replace() to clean strings from 
control characters and, under XP I found that some utf-8 
characters are also modified although they don't contain 
control characters (\x-\1f and \7f) at all.

Same code seems to work properly under MacOS X and linux.

Please note that code below is utf-8 and should be pasted with 
the editor in that mode. The char failing seems to be the 
upper i with dieresis: ?

The example include the non-working example (first) plus two 
alternatives that work properly under XP.

Ciao :-)

Reproduce code:
---------------
<?php
    $orig = "II????";
    $dest = preg_replace("/[[:cntrl:]]/","",$orig);
    echo $dest;
    echo "\n<br>\n";

    $orig = "II????";
    $dest = ereg_replace("[[:cntrl:]]","",$orig);
    echo $dest;
    echo "\n<br>\n";

    $orig = "II????";
    $dest = preg_replace("/[\x-\x1f]/","",$orig);
    echo $dest;
    echo "\n<br>\n";
?>

Expected result:
----------------
Should return

II????

in the three alternatives.

Actual result:
--------------
This returns:

II????    <--- incorrect
<br>
II????    <--- correct
<br>
II????    <--- correct
<br>