CheckBox Objects on secondary Accordian Panes are Null Objects.

Steps to reproduce:
1. Compile SWF using Flash Builder 4.0.4 build 277662, Flex SDK 4.1 build 16076
2. Run SWF
3. The CheckBox object on other than the first Accordian pane cannot be Initialized or any property set, instead getting: TypeError: Error #1009: Cannot access a property or method of a null object reference.

Actual Results: All CheckBox objects other than on the first pane are Null.

Expected Results: All CheckBoxes should be addressable.

Workaround (if any): Unknown.

This error occurs for MX and Spark CheckBox objects. This error was not present in Flex Builder 3.