I think if you decided to go with Struts2, you will have to re-write the majority of your application.
Struts2 is a different beast from Struts1 (but also, it is alot better).
What about your team ?
Are they familiar with Struts2 ?
The original was written using struts and Velocity. Therefore I suspect
that most of the code will have to be re-written. I've used struts 1.3 for several months now; the rest of the team will be swotting up on whatever
option we go for.
Struts 1.3 seems attractive since it is a mature technology and there are
a lot of resources available which would facilitate development and maintenence significantly. My concern would be that 2.0 is relatively new
and therefore may experience the typical life cycle of new technologies, wherein the first few years are spent solving defects or finding temp
solutions until the defects are resolved. However I understand the 2.0
is based on WebWorks and therefore it may not experience the usual gut of
defects associated with newer technologies.
regards,
Mo