code: public byte[] getFrameData(String id)
  	{
  		if (frames.containsKey(id))
  		{
  			return ((ID3v2Frame) frames.get(id)).getFrameData();
  		}
  
  		return null;
  	}
docs: Returns the data found in the frame specified by the id.  If the frame
  doesn't exist, then a zero length array is returned.
  
  @param id the id of the frame to get the data from
  @return the data found in the frame