Device files not good after umount

Yeah, this is UDF related, but I can't find the UDF mailing list and I know BF follows this list. I can create, list and delete device files on a packet-writing CDRW, but after I umount and mount again, they become completely inaccessible: ls: /cdrw/dev/ttyS0: Permission denied I can't delete them and 'rm -fr /cdrw/dev' hangs and doesn't respond to kill -9. This is with kernel 2.4.20, the packet patch dated Jan 05 and CVS UDF. Everything else looks good. - Jim