BIT-Wise Aggregation

Hi,

I have the following three tables :
Account (Id int, AccountName nvarchar(25))
Role (id int, Rights int)
AccountRole (AccountID, RoleID)

In Role table - Rights Column is a bit map where in each bit would refer to access to a method.
One account can be associated with multiple roles - AccountRole table is used for representing the N:N relation.

I want to develop a store procedure - which would return all AccountName and their Consolidated Rights.
Basically I want to do a BitWise OR operation for all the Rights in the Aggregation instead of the SUM as shown in the following statement.

SELECT Account.Name, SUM(Role.Rights) FROM Account WITH (NOLOCK)
JOIN RoleAccount ON RoleAccount.AccountID = Account.Id
JOIN Role ON RoleAccount.RoleId = Role.Id
GROUP BY Account.Name

Thanks,
Loonysan