Bug 158662 Image constructor is incomplete
The Image constructor Image(IImageContent) does not copy the imageMap member of IIMageContent. This can lead to bugs whereever the IImage interface is used to retrieve the Chart Image Map.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/Image.java
*            the source stream
	 * @param tgt
	 *            the target stream
	 * @throws IOException
	 */
	protected void copyStream( InputStream src, OutputStream tgt )
			throws IOException
	{
		
		byte[] buffer = new byte[1024];
		int size = 0;
		do
		{
			size = src.read( buffer );
			if ( size > 0 )
			{
				tgt.write( buffer, 0, size );
			}
		} while ( size > 0 );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.engine.api.IImage#getExtension()
	 */
	public String getExtension( )
	{
		return extension;
	}
}