public synchronized void removeUnsafeToCopyPrivateChunks()
	{
		List<String> newChunkType = new ArrayList<String>();
		List<byte[]> newChunkData = new ArrayList<byte[]>();

		int len = getNumPrivateChunks();
		for (int i = 0; i < len; i++)
		{
			String type = getPrivateChunkType(i);
			char lastChar = type.charAt(3);
			if (lastChar >= 'a' && lastChar <= 'z')
			{
				newChunkType.add(type);
				newChunkData.add(getPrivateChunkData(i));
			}
		}

		chunkType = newChunkType;
		chunkData = newChunkData;
	}