* @see SipServletMessage#getParameterableHeader(String)
*/
public Parameterable getParameterableHeader(String name) throws ServletParseException
{
Buffer buffer = SipHeaders.CACHE.lookup(name);
HeaderInfo hi = SipHeaders.getType(buffer);
if (hi.getType() != HeaderInfo.PARAMETERABLE && hi.getType() != HeaderInfo.ADDRESS && hi.getOrdinal() != -1)
throw new ServletParseException("Header: " + name + " is not of parameterable type");
Parameterable p = getFields().getParameterable(buffer);
if ((isSystemHeader(hi) || isCommitted()) && p != null)