check proxy on yast -> network services
Had the same problem for many many days.
Read much like disabling ipV6,tried to modify /etc/youservers ,turn off firewall but all did no good..
Strange thing was i have a home network with 3 suse 9.3 pcs and the others updated o.k (all pcs installations were from the same 5 suse 9.3 ftp iso cds).Also i had no problem browsing the internet,and firewall is turned off on the system with the online update problem (there is a firewall on the adsl gateway).
Finally I noticed on
Yast -> NetWork services -> Proxy
there was my previous proxy set there.
Set it up to use no proxy ,(connection throuhg adsl gateway).
It gave me a message like YOU is set to take the changes automatically but for other programs like wget,lynx you must log off and log in.
Ok i said nice run online update once more , same shit again : couldn' t connect to host
log off and log in ..
Bingo YOU works.
Hope this is the case