Mart5.1: Please use quote tags. It's so much more intuitive to read your post.

If the apps don't work well, they don't work well - or if they don't work over 3G, they don't work over 3G - but I have yet to see a single app on the N900 that is INTENTIONALLY made to work only over WiFi, or only over 3G. That is the issue. If zoutube and groove break over 3G, with a proxy server connection, that is either because of some problem in your 3G network provider's configuration, between the server and 3G, or some complicated combination there-of.

Plus, there's a difference between crippled (which I use to mean intentionally disabled) over any 3G in general, vs. having a bug that makes a complicated route of 3G -> proxy server -> elsewhere not work. Major difference. (Seriously, how many iPhone apps even let you configure them to use a proxy server?)

You're right, that does mean that the N900 can't do EVERYTHING it can do over WiFi over 3G. But it's a bug, largely linked, I suspect, to the 3G network and how it interacts with the N900 and proxy server. It is not an intentional block built into the device or the app. It's not an inability of the N900. It's at worst a screw-up in the app, but most likely a problem somewhere along the 3G network.