Bug 120503 Cascading Parameter can not drop into layout
Details: Cascading Parameter can not drop into layout Step: 1.Open a report design and Create a Sample Data Source and data set by "select * from CLASSICMODELS.CUSTOMERS" 2.New a cascading parameter and create CUSTOMERSNUMBER and CUSTOMERSNAME in parameter named number and name. Press OK 3.Drop parameter name into layout. Actual results: The parameter in Cascading Parameter Group can not drop to layout
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DEUtil.java
{
		try
		{
			Integer.parseInt( val );
		}
		catch ( Exception e )
		{
			return false;
		}
		return true;
	}
	/**
	 * Checks if the value is a valid number, including any integer and float,
	 * double.
	 * 
	 * @param val
	 */
	public static boolean isValidNumber( String val )
	{
		try
		{
			Double.parseDouble( val );
		}
		catch ( Exception e )
		{
			return false;
		}
		return true;
	}
	/**