I agree with BSlack on the modules issue. It sounds to me like the upgrade either:
1) installed a new kernel + sources + modules, but didn't have the same functionality as you wanted it to.
2) installed a new kernel + sources but no modules at all.
I thought you may have had your /lib/modules/2.4.22* tree still lying around (hence the suggestion for the 2.4.22 bare.i kernel bootdisk), but that doesn't appear to be the case
Anyway, you wanted a 2.4.23 kernel anyway, right? You have everything you need since the sorces are installed!