should /var/spool/mail/ have a the sticky bit set? ...

[Walter Tautz <wtautz@math.uwaterloo.ca>]

i am getting mailbox locking problems
here is an 

strace mail

<SNIP>

open("/var/spool/mail/<myhostname>.cf86b", O_WRONLY|O_CREAT|O_TRUNC|O_EXCL|O_SYNC, 0) = -1 EACCES
(Permission denied)
setgid(1000)                            = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
write(2, "Unable to lock mailbox: Permissi"..., 42Unable to lock mailbox: Permission denied
) = 42
close(3)                                = 0
munmap(0x400f5000, 4096)                = 0
munmap(0x40015000, 4096)                = 0
munmap(0x40014000, 4096)                = 0
_exit(0)                                = ?


ls -l /var/spool/mail
drwxrwsr-x    2 root     mail         4096 Mar 30 11:13 ./

On Solaris and /var/mail has a sticky bit set 
ls -ald /var/mail/
drwxrwxrwt   3 root     mail         1024 Mar 30 11:15 /var/mail/