Hello
I refer to my posting
http://www.mail-archive.com/grml@mur.at/msg00781.html
in which a whole discussion thread deals with the subject. It had also been relayed to the maintainers of x-servers x.org
IMHO the nohwcap issue shall be dealt with only by the kernel and / or any other hardware related software, which are currently the Xserver and the drivers only (in case of insertion / removal of hw). No application should try to find something out about hardware. Kernel shall do it once after booting, insertion or removal of hw only and then hold the data in its virtual filesystem.
then such a weird device as /etc/ld.so.nohwcap is at best not existing or second best once read updated during system boot, insertion or removal of hw.
best regards a system engineer