DotNetNuke UserController.GetUser(PortalId,UserId, False) inside TransactionScope throws TransactionAbortedException

Question

Either DotNetNuke UserController.GetUser(PortalId,UserId,false) or UserController.ValidateUser(...) inside TransactionScope is causing TransactionAbortedException and the innerException is TransactionPromotionException. The symptoms are the same as this.

Could anyone suggest me the solution to this issue? Thanks a lot !

using (System.Transactions.TransactionScope ts = new System.Transactions.TransactionScope())
    {
        DotNetNuke.Entities.Users.UserInfo ui = DotNetNuke.Entities.Users.UserController.GetUser(PortalId, UserId, false);         
        ts.Complete();
    }