[CentOS] missing from Centos51 src tree: ".../drivers/infiniband/hw/amso1100/Makefile"

i'm attempting to rebuild centos51 kernel-xen. (fwiw, because pciback has NOT been compiled into the kernel, http://bugs.centos.org/view.php?id=2767) after, yum install kernel-devel kernel-xen-devel and usual, ln -s /usr/src/kernels/`uname -r`-`uname -m` /usr/src/linux

[CentOS] Re: missing from Centos51 src tree: ".../drivers/infiniband/hw/amso1100/Makefile"

checking further for the Makefile in the latest git repo, git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband.git for-linus , there's also no Makefile in the respective directory, ./for-linus/drivers/infiniband/hw/amso1100/ emailed the repo maintainer to ask, "is this an omis