I tried to do yum update and got this response.

[root@localhost ~]# yum update
Loading "kernel-module" plugin
Setting up Update Process
Setting up repositories
Reading repository metadata in from local files
Excluding Packages in global exclude list
Finished
Resolving Dependencies
--> Populating transaction set with selected packages. Please wait.
---> Package evolution.i386 0:2.12.3-8.el5_2.2 set to be updated
--> Running transaction check
--> Processing Dependency: libegroupwise-1.2.so.13 for package: evolution
--> Processing Dependency: libnssutil3.so for package: evolution
--> Processing Dependency: libexchange-storage-1.2.so.3 for package: 
evolution
--> Processing Dependency: libgtkhtml-3.14.so.19 for package: evolution
--> Finished Dependency Resolution
Beginning Kernel Module Plugin
Finished Kernel Module Plugin
Error: Missing Dependency: libegroupwise-1.2.so.13 is needed by package 
evolution
Error: Missing Dependency: libnssutil3.so is needed by package evolution
Error: Missing Dependency: libexchange-storage-1.2.so.3 is needed by 
package evolution
Error: Missing Dependency: libgtkhtml-3.14.so.19 is needed by package 
evolution
[root@localhost ~]#

I am using the vanilla yum configuration obtained from clean SL 5.1 
install. What am I missing?

Thanks,
Al