Help with this problem of font after upgrading to 3.6.5

[ValkyrieLenneth]

I have just upgraded my forum from 3.5.3 to 3.6.5 and this wierd error appeared.
The problem is i cant see it my self, i'm using windows vista and ie7. Problem reports come from users who are using IE6 and Windows XP. I remember that someone has posted the same error here but cant find the thread anywhere.
Not sure if this is the problem of style or not because when i set the accessibility in IE's option to Ignore the font style, everything seems to be ok.
I love this style of allan, so please help me. Thank you so much T_T

[ValkyrieLenneth]

My forum link is www.xtremevn.com/forum

I'm using the ISO-8859-1 charset, most of ppl here are using UTF-8, is there anyway to convert the database or quickfix for this ?
Update: Firefox, Opera, IE7 are ok, IE6 has problems T_T.

[Dismounted]

Custom settings in IE probably affect it.

[ValkyrieLenneth]

Thank you for replying but all of them said that they didnt change anything in IE6 setting, seems that IE7,FF and Opera got better character encoding automated system ? :(
BTW: I deleted the trebutchet font from the style and it seems to be ok right now.

[Dismounted]

IE6 defaults to a different encoding system maybe?

[ValkyrieLenneth]

I think the problem is those XP PCs dont have trebuchet MS font. I have changed the Forumhome font to tahoma -.-