disapearing usb path

Hello,

we are observing a strange behaviour regarding pcsc-lite-1.1.2-beta4 in 
connection with /proc/bus/usb (usbdevfs).
When starting pcscd on boot it first works as suggested, but after a few 
minutes pcscd complains about not being able
to open /proc/bus/usb/XXX ("USB path seems to have disappeared"). But 
when examining this path from commandline
(ls, etc.) everything looks allright. Trying to connect with pcsc_scan 
leads to pcscd syslog entries telling us, that there are
no filehandles left. As a consequence the pcscd usb hotplugging is 
disabled.

We are using kernel 2.4.21 with bluetooth-patch mh2 and kmesg-patch. 
Hotplugging is enabled and our cardreader is a
cm2020. The readerdriver sometimes is unloaded before the usb-error 
occurs  and sometimes it is still functional (ATR is
still read and logged by pcscd), but pcscd cannot manage to dispatch 
messages to it.

Has anyone seen this kind of behaviour?

Thanks in advance for any help!

Kind regards
Dominik Fischer