etiennejava - 2007-07-31

We're currently using Struts version 1.2 (I believe).
I recently purchased a Struts manual that includes 1.3, but it doesn't specify which parts are new in 1.3.
I'm not looking to get into a discussion here on which book is best, etc.
Is there a godd reference site that has the difference between 1.2 and 1.3?
On a related note, our project includes 'struts.jar'.
What's the best way to determine which Struts version is in the jar?
The 'license' file contains 'version 2.0', so I'm guessing it refers to Struts 1.2.
If we switch to the struts jar for 1.3, is it upwards compatible,
so that all our current code developed under 1.2 should work as before?
I don't really want to jump to Struts 2.X: might be too big of a change.