Description:
------------
Hello,

The function strtoupper is NOT functioning properly with Cyrillic on ALL of our domains. 

<?
echo strtoupper("?? ??????");
?>

When you search for term or phrase with capital letters and search for the same term or phrase in low cap, it appears that the results are completely different (they shouldn?t be). 

For instance: search for "?? ??????" and then try searching for "?? ??????" to see what I mean. Click on the links below and see the search results: 

http://www.yanbibiyan.com/articlesearch.php?str=??%20?????? 
http://www.yanbibiyan.com/articlesearch.php?str=??%20??????

Any suggestions how this issue can be corrected would be gladly appreciated?

Please advice?

Thanks
Bob



Reproduce code:
---------------
<?
echo strtoupper("?? ??????");
?>

Expected result:
----------------
?? ?????? 

Actual result:
--------------
see description above