code: private static StringBuffer doAppendComment(StringBuffer buffer, String comment)
  	{
  		buffer.append(SEQUENCE__COMMENT__OPEN).append(comment).append(SEQUENCE__COMMENT__CLOSE);
  		return buffer;
  	}
docs: Add a comment to a StringBuffer.
  
  If the buffer is null, a new one is created.
  
  @param buffer
  StringBuffer to fill
  @param comment
  the comment
  @return the buffer