VFS(?) weirdness

  Dear collegues,

  I've got a box running HEAD where a strange bug is observed. The below
script always returns on this box:

pwd: .: Permission denied

The box doesn't have any unusual things in its kernel config. No sysctl
tuning. The filesystem is UFS. The bug can be reproduced in any user
readable and writable directory, all commands except pwd execute
successfully.

The script should be run from current directory. 

%%%
#!/bin/sh

dir=$(mktemp -d $0.XXX)
cd ${dir}
dir2=$(mktemp -d $0.XXX)
rm -rf ${dir2}
/bin/pwd
cd ..
rm -rf ${dir}

-- 
Totus tuus, Glebius.
GLEBIUS-RIPN GLEB-RIPE