OpenVAS 4 has landed in UNSTABLE in OBS

Add this to your sources.lst:

deb http://download.opensuse.org/repositories/security:/OpenVAS:/UNSTABLE:/v4/xUbuntu_10.10/ ./

Then you need to get the key and add it to apt:

wget http://download.opensuse.org/repositories/security:/OpenVAS:/UNSTABLE:/v4/xUbuntu_10.10/Release.key
apt-key add Release.key
rm Release.key

Then just

apt-get update