The only reason that I can imagine is that you downloaded the wrong rpm. Or you have updated xorg packages that are not part of the standard distribution.
The package fontconfig-devel is available from the SUSE server. If YaST doesn't resolve this dependency automatically, you can download it e.g. here:
ftp://ftp.sunet.se/pub/Linux/distrib...218-8.i586.rpm
I guess you could save a lot of work if you add a FTP server to your YaST sources.