custom kernel and agpgart as a module

[Endymion]

Hey folks,

I'm using the nvidia diplay drivers and I would like to be able to use
NvAGP on my machine. However, both the stock fedora kernel and all of
the 2.6.12.rcx+mm kernels that I have compiled do not compile agpgart as
a module.  For the custom kernels even editing the .config file manually
to set agpgart as a module does not work.  Anyone know why this is or a
way around it?
Thanks,
Endy