Description of problem:
Well, the URL from Source0 doesn't exist simply (ends in 404 not
found) and the onliest similar page I found was "The Linux Frame 
Buffer Device Subsystem" which has a few information about it and
could be the "homepage".

Version-Release number of selected component (if applicable):
fbset-2.1-15

Actual results:
Either you remove the full URL by the package name only or you can
use the solution below. BTW, at the URL I used, there are some 
"newer" (1999, too but from July and August) test versions available.
Maybe you've got a look to the changes between them and 2.1...

Expected results:
--- fbset.spec          2004-02-13 20:31:04.000000000 +0100
+++ fbset.spec.rsc      2004-04-30 20:11:22.000000000 +0200
@@ -4,7 +4,8 @@
 Release: 15
 Copyright: GPL
 Group: Applications/System
-Source: http://www.cs.kuleuven.ac.be/~geert/bin/fbset-2.1.tar.gz
+URL: http://home.tvd.be/cr26864/Linux/fbdev/
+Source: http://home.tvd.be/cr26864/Linux/fbdev/%{name}-%{version}.tar.gz
 Patch0: fbset-2.1-makefile.patch
 Patch1: fbset-2.1-fixmode.patch
 BuildRoot: %{_tmppath}/%{name}-root