public Long getLongValue( String key ) {
	if( key == null )
	    return null;

	HTTPHeaderLine hl = this.get( key );
	if( hl == null )
	    return null;

	if( hl.getValue() == null || hl.getValue().length() == 0 )
	    return null;

	try {
	    return new Long( hl.getValue() );
	} catch( NumberFormatException e ) {
	    return null;
	}
    }