mount XFS 64KB block size cause "Function not implemented"

mount xfs with 64kb blocksize...
http://www.groupsrv.com/linux/about161614.html

Re: mount: Function not implemented?
http://oss.sgi.com/archives/xfs/2004-07/msg00524.html

Not on linux, it can only do filesystem blocksize upto pagesize.
So on ia32 it maxes out at 4K.

XFS: A high-performance journaling filesystem
http://oss.sgi.com/projects/xfs/

Filesystem Block Size

The minimum filesystem block size is 512 bytes. The maximum filesystem block size is the page size of the kernel, which is 4K on x86 architecture and is set as a kernel compile option on the IA64 architecture (up to 64 kilobyte pages). So, XFS supports filesystem block sizes up to 64 kilobytes (from 512 bytes, in powers of 2), when the kernel page size allows it.