I use virtualdub a lot for compression,tv capture(bt848) and editing,and i've come to notice something very interesting.Divx3.22 gives almost always better results than all new divx versions(including divx5).
3.22 provides a smoother picture with less artifacts.even with gmc,qp and bd turned on 3.22 still gives better quality than divx5. only at birates less than 150 kb/s does divx5 shine.i'd like to see THG writing an article comparing the end quality of encoded movies using both versions at the same bitrate.

I've never come across a divx3.22.

Divx3.11a - yes
Divx4.xx - yes
Divx3.22 - no

Unless you mean one of those dodgy hacked scene-change codecs?

In which case, you're better off using 3.11a and Nandub. You're probably better off using Nandub rather than Virtualdub if you're only playing with divxs anyway (they're pretty much the same program - but you can do cool things like mux vbr .mp3 etc)