Forum Characters like ě?čřř????é in url

[محروم.كوم]

Hi*
I upgraded my forum to Vbulletin4 today and set Friendly URLs to **Mod Rewrite Friendly URLs**. This works good but all urls look

http://ekucharka.net/vbulletin4/thre...ekuchařky


but i would like url without ě?čř????é and with by all small words

for example: http://ekucharka.net/vbulletin4/thre...anky-ekucharky

Thank you for your reply and merry christmas.
Jarda __DEFINE_LIKE_SHARE__