sounds like you don't serve your content as utf-8. do this by setting the correct header:
header('Content-type: text/html; charset=utf-8');
in addition to be really sure the browser understands, add a meta-tag:
<meta http-equiv="Content-type" content="text/html; charset=utf-8" />
note that, depending on where the text comes from, you might have to check some other things too (database-connection, source-file-encoding, ...) - i've listed a lot of them in one of my answers to a similar question.
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