I've been trying to place a firewall on my Suse and failed

1. Tried OpenSuse 11 but in Yast there is no option for Firewall and if I try to install the modules it simply fails to connect to download.opensuse.org (thought ping is working)

2. Tried OpenSuse 10.3 but (which has firewall modules in Yast) if I activate the firewall (with SSH/port 22 made available) the next time I need to connect to the account fails - is like port never really got open.

Any suggestion as how I might be able to have a decent firewall greatly appreciated.