how to require a kernel module

hi,
on rhel/centos-5w we've a lot's of kernel module (thanks to the elrepo) 
and we can build our own on a nearly standardized way for rhel/centos. 
but i now run into a problem how to add a require kmod line into another 
package's spec file. it seems to very easy, if i've got package x.spec:
Requires: y-kmod
first question whether y-kmod or kmod-y (tha package name or the virtual 
provides)? and if we go a bit further and have a i386 machine with 4gb 
ram which install by default kernel-PAE and like to install x into that 
machine i wish to pull (yum pull) kmod-x-PAE and not kmod-x since it 
can't be used on a PAE kernel. what's more if x pull kmod-y that also 
pull the none PAE kernel too which is also not a good think. there are 
two plugins in yum-utils yum-kernel-module and yum-fedorakmod, but none 
of the seems to working (yum-fedorakmod instal the proper kmod-x-PAE too 
if i set installforallkernels=1, but still install the non PAE one and 
the none PAE kernel too).

so what's the good and proper solution to require y kernel module into 
package x (in a way that works with yum on all kernel variant)?

i even like to modify any of the yum-kernel-module or yum-fedorakmod to 
be able to use, but the problem is that i can't write conditional 
requires in a package spec file which depend on the runtime kernel 
variant:-(

anybody has any solution to this?

-- 
   Levente                               "Si vis pacem para bellum!"