Weird charactars in output

Hi there, This is small part of my code: $output .= ("http://foo.bar.net/get_attachment?type=attachment&list=$listname&msg=$ msgid " . $parts['attachments_name'][$i] . "<br>"); But to my surprise the output it creates is: http://foo.bar.net/get_attachment?typeïtachment&list=mimetest&msgOfilena me.tar.gz What could be the problem? It's not the browser as far as I know, because if I view the source of the page, it also has the weird characters. Also tried different browsers on linux & win32 platforms (you never know) and every time the same result. Thanks, Jeroen