G2, Mambo, and charset

I am having problem with G2 integrated into Mambo. Everything runs fine except the encoding is all wrong for the mambo's content, all the letter appear incorrect. When I right click on the page, choose "Encoding", then "Western European (ISO)" , then everything in Mambo displayed correctly.

Some might says I got to change Mambo's encoding to Utf-8, but I really cannot do that because then I and all the site's users will have to resubmit their posts again. Please help, I've got really stuck and no search in this forum or the net help me find the right solution. Thanks in advanced.