Implicit coercion of a value of type Namespace to an unrelated type Namespace

This is all using Build 4.0.13288 and AIR 2 Beta 2

Steps to reproduce:
1. Create a Flex Library Project with including Air Runtimes
2. Create an second Flex Library Project without including Air Runtimes
3. Include the first project in the second.
4. Use the Namespace class in both projects.

Actual Results:
1067: Implicit coercion of a value of type Namespace to an unrelated type Namespace.

Expected Results:
No Error

Workaround (if any):
Include the Air Runtimes in the Flex Library Project.