Bug 90521 [Import/Export] NumberFormatException during import zip file
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/wizards/datatransfer/TarInputStream.java
* Creates a new tar input stream on the given input stream.
	 * 
	 * @param in input stream
	 * @throws TarException
	 * @throws IOException
	 */
	public TarInputStream(InputStream in) throws TarException, IOException {
		super(in);
		
		
		firstEntry = getNextEntry();
	}
	/**
	 * Create a new tar input stream, skipping ahead to the given entry
	 * in the file.
	 * 
	 * @param in input stream
	 * @param entry skips to this entry in the file
	 * @throws TarException
	 * @throws IOException
	 */
	TarInputStream(InputStream in, TarEntry entry) throws TarException, IOException {
		super(in);
		skipToEntry(entry);
	}
	/**
	 *  The checksum of a tar file header is simply the sum of the bytes in
	 *  the header.
	 * 
	 * @param header