If I understand the library it is meant to be used on i?86 and x86_64 platforms only. If I am right then it is more efficient to use ExclusiveArch because in current situation every secondary arch must add an exception into the ExcludeArch. this is the suggested form: ExclusiveArch %{ix86} x86_64
This bug appears to have been reported against 'rawhide' during the Fedora 11 development cycle. Changing version to '11'. More information and reason for this action is here: http://fedoraproject.org/wiki/BugZappers/HouseKeeping
No, this package should build (and work) on all arches. That it doesn't is an entirely separate pile of bugs.