Permits Determination Using Multiple Classes

Dear SAP Gurus,

I do know that when we are defining a permit group, it can only be allocated one class and the characteristics of that class are used for the automatic determination of the Permit, but what if i want to determine permits using the characteristics of different classes. Can it be possible? I know one way of going around the problem is to create all the characteristics I want to use in the same class and then assigning them to the Permit Group. But can multiple classes be used?

Regards,

M. Usman Kahoot