Hi! I should add that on IA-32 there is no similar fallback either. If you create say i586 version of a library and want to to be usable for i686 as well, one needs to create /usr/lib/i586/libfoo.so /usr/lib/i686 -> i586 (or /usr/lib/i686/libfoo.so -> ../i586/libfoo.so ). Jakub