How to use Multiple dimension in named Sets?

Hi,

When I execute the below mdx query I get expected result set,

WITH SET [Paid] AS  
([SeatGroup] * [CLS] * [Account].[Is Internal].&[False])
Select [Measures].[UserId Distinct Count] on Columns,
[paid]  on Rows FROM [GlobalEnglishDWCube]

But when I use the expression in Named Set in OLAP Cube design, I face error:

named set expression:  "([SeatGroup] * [CLS] * [Account].[Is Internal].&[False])"

CLS and SeatGroup are named sets available in cube.

Please give suggestion.