Comment 2 for bug 531178

I think this bug shows the need to have some kind of backwards compatibility documentation and runtime checks. Version 0.6.x is more than happy to continue backing up to a set created by 0.4.x. If I didn't need to restore a file, I could have gone years before realizing that I may have problems restoring my data. Furthermore, what happens if the next version introduces something that version 0.4.x can't handle, and I continue with the backup set created by 0.4.x? Then both versions won't be able to read the backup set.