I recently secured my /tmp partition, and now I get an error when I try to view the user permissions in mysql from the webmin panel. The exact error is:

SQL desc `user` failed : Can't create/write to file '/tmp/#sql_331d_0.MYI' (Errcode: 13)

any idea how to get around this?

/tmp requires 777 permissions

If you want to secure it use:
/dev/hdd7 /tmp ext3 noexec,nosuid 0 0

in your fstab -- make sure you use the right dev and not mine.