Can't help you with your first question, but for your second:

>An another problem: How can I make bigger the /tmp directory?
>Some programs which use it are cancelled with "file system full".

     I made a /usr/tmp directory and symlinked /tmp to it.

 [ziggy 52] ls -ld /usr/tmp
drwxrwxrwx  3 root  35  512 Feb 15 15:04 /usr/tmp/
 [ziggy 53] ls -ld /tmp
lrwxr-xr-x  1 root  wheel  8 Feb  9 13:13 /tmp@ -> /usr/tmp

     Never had any problem.

-Tom / tms