We are in the beginning of the migration to struts2 and it seems like there will be some period when both frameworks will be active at the same time..the only problem now is accessing the session beans managed by struts2 in struts1 and vice-versa form beans from strut1 mapped in struts2 . Half of the jsp would use struts1 tags and other half struts2 tags. So there should be beans instantiated in both frameworks.
Probably struts2 bean can be injected to struts1 action with struts1 form still accessible as execute() argument, but what about other way? accessing struts1 form bean (not just data, but managed bean) in struts2 execute() ?