Bug 173582 Run servlet should not be affected by values in document.[0000]
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/taglib/AbstractViewerTag.java
* @param src
	 * @param target
	 * @throws Exception
	 */
	protected void __handleIFrame( String src, String target ) throws Exception
	{
		JspWriter writer = pageContext.getOut( );
		
		String paramContainerId = "params_" + viewer.getId( ); 
		writer
				.write( "<div id=\"" + paramContainerId + "\" style='display:none'>\n" ); 
		Iterator it = viewer.getParameters( ).values( ).iterator( );
		while ( it.hasNext( ) )
		{
			ParameterField param = (ParameterField) it.next( );
			
			String encParamName = ParameterAccessor
					.htmlEncode( param.getName( ) );
			
			String paramValue = DataUtil.getDisplayValue( param.getValue( ) );
			
			if ( param.getValue( ) == null )
			{
				writer
						.write( "<input type = 'hidden' name=\"" + ParameterAccessor.PARAM_ISNULL + "\" \n" ); 
				writer.write( " value=\"" + encParamName + "\">\n" ); 
				continue;
			}
			
			writer