vB4.2.0 change my words with accent
 

Hi guys, i've bought vBulletin 4.2.0 license forum, i've installed it, and because i'm Italian, in my language there's so much words with accent, and if i try to write a post when i public it all the words with accent change in ascii code i think like this: "più" <--- if you can see your board fixed it automatically, why my not? and i've this: "pi&#24'9;"
i've also changed my char set from ISO-8859-1 to UTF-8 and latin1 , but nothing..

How can i fix it?

Edit: my tables is charset: UTF-8 and Collation: utf8_general_ci but if i select utf-8 in language i see a point of question in all words with accent

Install the language pack for your country

i've just do this but nothing.. the error persists