Bug 146796 Error message pop up if display text contain non-digital char when add next item
Description: In decimal type parameter creation,display type is "list box", Error message pop up if "display text" contain non-digital char when add next item. Steps: 1.Create a new decimal parameter 2.Set display type as "list box" 3.Input one item: value:1, display text:test 4.Input another item: Value:2 Actual result: error message pop up: The display text already exists! Expected result: Input item succussfully.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
}
	};
	private ITableLabelProvider labelProvider = new ITableLabelProvider( ) {
		public Image getColumnImage( Object element, int columnIndex )
		{
			if ( valueTable.getColumnProperties( ).length == 4
					&& columnIndex == 1 )
			{
				SelectionChoice choice = ( (SelectionChoice) element );
				if ( isDefaultChoice( choice ) )
				{
					return DEFAULT_ICON;
				}
			}
			return null;
		}
		public String getColumnText( Object element, int columnIndex )
		{
			SelectionChoice choice = ( (SelectionChoice) element );
			final int valueIndex = valueTable.getColumnProperties( ).length - 2;
			String text = null;
			if ( valueTable.getColumnProperties( ).length == 4
					&& columnIndex == 1 )
			{
				if ( isDefaultChoice( choice ) )
				{
					text = FLAG_DEFAULT;
				}
			}
			else if ( columnIndex == valueIndex )