title: char encoding used in individual fields of certificate
body: <p>Its not clear to me where does the information of character encoding (AsciiString, BMPString, UTF8String etc)  used inside the individual fields of an X509 certificate (common name etc. <a href="http://www.ietf.org/rfc/rfc5280.txt" rel="nofollow" title="rfc5280">rfc 5280</a> ) comes from.
  We definitely can't be sure just looking at the individual character stream ( unless it's Unicode ).
  Does x509 certificate contains information about character encoding elsewhere?</p>