Hi there,
just a short summary of my latest results.
I use a logitech quickcam 9000 pro on an up-to-date gentoo linux with 2.6.18-suspend2 kernel, old nvidia graphics card with 3D-support by the driver.
After some investigations and tests I got it working, including the camera's microphone.
The kernel setup / module installation was done as described here:
http://de.gentoo-wiki.com/Logitech_Quickcam_connect
I checked both with luvcview and ekiga before using skype. Ekiga finds the video device, and so does skype. Skype also find the usb microphone without any tricks.
The main problem for me was that obviously the 9000 pro has a problem with framerate switching.
As indicated the solution was to take a current UVC driver. Before that I had lots of problems both with audio and video in a skype-call, as many other described here in the forum. Now it's fine.
It seems that there is light at the end of the tunnel :-)
HTH
P.S.: Is there a way to set the webcam resolution or other video parameters ?
P.P.S.: videoecho123 seems to work, at least sometimes