I think I should add that dyna forms seems to be a bit more prone to trouble with your
IDE.
If you're using Eclipse and
JBoss they can sometimes cause errors for no real reason .
In my case, everytime I change a dynaform, I have to delete several xml files, shut down Eclipse, start it back up, and run XDoclet.
If I don't do that, I'll keep getting "Invalid Property Name" errors.
I suggest that you start with dyna's and if they give you problems,
test out the same form as an ActionForm.