I don't understand why rpm is complaining about breaking a dependency, when the package being removed doesn't provide said dependency:
[root@mother root]# rpm -e kernel-smp-2.4.21-gg3 error: Failed dependencies: kernel-smp = 2.4.21-gg2 is needed by (installed) NVIDIA_kernel-2.4.21-gg2-smp-1.0-4363gg10 kernel-smp = 2.4.21-gg2 is needed by (installed) bcm5700-2.4.21-gg2-smp-6.2.11-gg3
[root@mother root]# rpm -q --whatprovides kernel-smp---------------------^^^^^^^
kernel-smp-2.4.20-8
kernel-smp-2.4.20-19.9
kernel-smp-2.4.21-gg2
kernel-smp-2.4.21-gg3
[root@mother root]# rpm -q --provides kernel-smp-2.4.21-gg3
kernel = 2.4.21
kernel-drm = 4.1.0
kernel-drm = 4.2.0
kernel-drm = 4.2.99.3
kernel-drm = 4.3.0
module-info kernel-smp = 20030716:2.4.21-gg3