Bug 195335 Multithreads issue
a static hashmap in class HTMLServerImageHandler has not been synchronized which may leads to that the same images are handled(eg: write to disk) multiple times.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/HTMLServerImageHandler.java
int size = 0;
			do
			{
				size = in.read( buffer );
				if ( size > 0 )
				{
					out.write( buffer, 0, size );
				}
			} while ( size > 0 );
			in.close( );
		}
		catch ( IOException ex )
		{
			throw new EngineException( MessageConstants.ERROR, ex );
		}
		finally
		{
			try
			{
				if ( in != null )
				{
					in.close( );
				}
			}
			catch ( IOException er )
			{
			}
		}
	}
}