b1 or b2?

I have only just gotten around to installing beta 2 on my Axim x50v, Windows Mobile 2003SE. I already had beta 1 installed and working, and making my life better. Thank you.
I ran the installer for beta 2. I used the default installation location, I think the same as I used for beta 1. Of course, I can't tell any difference by looking, but in Options > About, I see "version 4.00 b1".
Does this mean that the beta 2 did not install properly? Should it be necessary to uninstall beta 1 before installing beta 2? I didn't think so.