[plug] Crontab Permissions

[Timothy White]

I'm having a problem on an Ubuntu box. On my desktop I can edit my own
crontab just fine with crontab -e
On my server (also a 'default' ubuntu install) the only user that can
change crontabs is root.
$ crontab -e
crontabs/tim: Permission denied
>From what I could see, there was no difference on the computers.
Nether had cron.allow or cron.deny. The perms on
/var/spool/cron/crontabs was the same.
I can't see any differences. I even tried adding a cron.deny file.
I couldn't see any setuid bits on the crontab executable on ether
machine, and an strace reveals very little.
open("crontabs/tim", O_RDONLY)          = -1 EACCES (Permission denied)
Which I'd expect because it's not runnign as a user with access to
/var/spool/cron
doing a strace crontab -l on my machine also shows
open("crontabs/tim", O_RDONLY)          = -1 EACCES (Permission denied)
at one point, but it can open my crontab, and list it and edit it!!

I'm not sure what to do, short of allowing all users access to
/var/spool/cron/crontabs.

Tim