Bug 143671 [Linux-As][Smoke]Parameter can't be used.
Details: [Linux-As]Parameter can't be used. Setp: 1.New a report design. 2.New a paremeter. 3.Preview and click Run Report Parameter. 4.Dialog pop up and press OK. Actual resutl: Report error.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
*            http request
	 * @param name
	 *            parameter name
	 * @param value
	 *            default parameter value
	 * @return new query string with new parameter value
	 */
	public static String getEncodedQueryString( HttpServletRequest request,
			String name, String value )
	{
		String queryString = ""; 
		Enumeration e = request.getParameterNames( );
		Set nullParams = getParameterValues( request, PARAM_ISNULL );
		boolean isFirst = true;
		while ( e.hasMoreElements( ) )
		{
			String paramName = (String) e.nextElement( );
			if ( paramName != null
					&& !paramName.equalsIgnoreCase( PARAM_ISNULL ) )
			{
				String paramValue = getParameter( request, paramName, false );
				if ( nullParams != null
						&& nullParams.remove( toUTFString( paramName ) )
						&& !paramName.equalsIgnoreCase( name ) ) 
				
				
				{
					paramName = urlEncode( paramName, ISO_8859_1_ENCODE );
					queryString += ( isFirst ? "" : PARAMETER_SEPARATOR ) + PARAM_ISNULL + EQUALS_OPERATOR + paramName; 
					isFirst = false;