Well not exactly Cabeza. It is true that there appears an incompatibility between IE7/8 ext, FO and NGINX.
There are many instances of this error being reported on the net. The consensus appears to be the following:
Variously reported under IE7 and 8: as errors in content type and/or characterset.
example fix:
php -> header("Content-Type: text/html; charset=ISO-8859-1");
html -> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
As you can see the fixes do not alter the ext code base. They alter the HTTP coding.
The problem, in this case, appears to be NGINX...that is the common factor. Does anyone else have an NGINX implementation?