I might be able to help you with your Joikuspot issue.

Correct me if I'm wrong: your client can connect to your N900 via wifi with Joikuspot on, but your client couldn't connect to the internet via your N900's 3G internet.

In this case you'd like to reload the module JoikuSpot_Bouncer:

Under terminal, as root, type:
The fact is that Joikuspot_Bouncer always dies. So you'd like to make an alias to reload it from time to time.

It's very annoying. Therefore I use other method to replace Joikuspot. I can tell you if you'd like to know how.