/var/log/maillog isn't updating. Postfix related

can someone please help me figure how i can get maillog to start updating again? it just all of a sudden stopped. and postfix isn't writing to it anymore. I'm running a Ubuntu box 8.04

thanks

Especially Postfix has great HOWTO-DEBUG document. You can follow the guidelines there, while making sure that no one has played with the file's permissions, etc. Start with postfix's restart, if feasible, and see if the file gets updated after test mail.

thanks a million for responding. i have tried quite a lot of things which includes rebooting the server, restarting postfix multiple times. manually rotating the logfile. none of which worked.

the maillog was working before but just stopped. below is the last errors that was written to the file.

Jan 8 03:14:01 nagios postfix/postdrop[30330]: warning: unable to look up public/pickup: No such file or directory
Jan 8 03:19:46 nagios postfix/qmgr[30377]: fatal: do not run this command by hand
Jan 8 03:19:58 nagios postfix[30378]: fatal: chdir(/var/spool/postfix): No such file or directory
Jan 8 03:20:02 nagios postfix[30379]: fatal: chdir(/var/spool/postfix): No such file or directory

keep in mind, i've been able to get postfix running and sending emails as it is expected to do. i'm just not seeing anything being written to the /var/log/maillog file. i want to be able to see the progress of whatever postfix is doing and it is in maillog file that it use to be in.