...cups-libs is installed, not cups.
and it is samba...
[root@sme7 ~]# rpm -q --provides cups-libs
libcups.so.2
libcupsimage.so.2
cups-libs = 1:1.1.22-0.rc1.9.10
[root@sme7 ~]# rpm -q --whatrequires libcups.so.2
samba-common-3.0.10-1.4E.6
samba-3.0.10-1.4E.6