Bug#518921: i386 missing syscall detection is broken on amd64

[Anders Kaseorg <andersk@MIT.EDU>]

This patch is included in today’s stable kernels 2.6.27.20 and 2.6.28.8.  
It has also been in the Fedora 9 and 10 kernel for a few weeks (Red Hat 
bug #484871).

Anders