Bug 154803 [regression]Cannot render document to user defined path through __document parameter
Description: Cannot render document to user defined path through __document parameter Steps to reproduce: 1. Preview a report in viewer 2. Modify url to add "__document=c:/tmp.rptdocument", this will generate report document to c disk with name "tmp.rptdocument" 3. Press enter. Expected result: Report displays correctly and the document is created. Actaul result: The document file : c:/tmp.rptdocument does not exist or contains errors.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/context/ViewerAttributeBean.java
* @return
	 */
	protected void parseConfigVars( HttpServletRequest request,
			Collection parameterList )
	{
		this.configMap = new HashMap( );
		
		String reportConfigName = ParameterAccessor
				.getConfigFileName( this.reportDesignName );
		if ( reportConfigName == null )
			return;
		
		SessionHandle sessionHandle = DesignEngine.newSession( ULocale.US );
		ReportDesignHandle handle = null;
		try
		{
			
			handle = sessionHandle.openDesign( reportConfigName );
			
			if ( handle != null )
			{
				String displayTextParam = null;
				Iterator configVars = handle.configVariablesIterator( );
				while ( configVars != null && configVars.hasNext( ) )
				{
					ConfigVariableHandle configVar = (ConfigVariableHandle) configVars
							.next( );
					if ( configVar != null && configVar.getName( ) != null )
					{
						String paramName = configVar.getName( );