I don't know of any easy way to use KDevelop/Designer 3 to create Qt 2 programs; the format of the .pro files is different (3.0 uses qmake, 2.0 uses tmake), and the format of Designer's .ui files is different as well.
I personally use Vim (gVim) for doing most of my coding, and Designer 2.x for some of my interfaces (though Designer 2.x is lacking in many areas). I don't use an IDE as I haven't found one that I like).
If you wanted to, you _could_ run Qt 3 apps on the Zaurus - someone made a build of the Qt library for the Z. However, it's not perfect - applications don't integrate quite as well with Qtopia as Qt 2 apps do.
- ashikase
anpachi, gifu, japan