Content-Type parsing issue

Hello all,

nginx-0.7.33
It seems than nginx cannot correctly recognize the following header:

Content-Type: text/html;UTF-8;charset=UTF-8

(Can be seen on http://www.nutrisystem.com/jsps_hmr/home/index.jsp
for example)

The following substitution never triggers:

proxy_set_header Accept-Encoding “”;
sub_filter ‘Enjoy’ ‘FOO’;
sub_filter_once off;

Can someone confirm the issue or should I upgrade to latest build?