symfony - credentials problem

I am trying to fully understand how the credentials/permissions system works in symfony(1.4)

I have 2 groups and 2 users.

User 1 has the following permissions: Add.Car, Delete.Car

User 2 has the following permissions: Add.Bike, Delete.Bike

Now what I want to do, is only allow users with the Add.x permissions to be able to add to a category table.

Th开发者_开发知识库e problem is, that If I have:

credentials: [Add.Car, Add.Bike] - it seems to look for users with BOTH of these, not either of them.

Is this how the credentials work and If so, is there a way to check if the user has either Add.Bike OR Add.Car before allowing them to create new records?

Thanks

---

Wrap the credentials in [ ]

credentials: [[Add.Car, Add.Bike]]

see http://www.symfony-project.org/jobeet/1_4/Doctrine/en/13 'Complex Credentials' section