[Dovecot] dovecot v1.2.10 + unknown mail_uid parameter

hi...

i upgrading dovecot from v1.0.7 to v1.2.10, so i perform some modifications (http://wiki.dovecot.org/Upgrading/1.1 and http://wiki.dovecot.org/Upgrading/1.2), but i have the following problem when i want to test installation:

in dovecot.conf, i set the user mail:

mail_uid= 72940
mail_gid= 72941

but when i try to start dovecot i have the following error:

# sbin/dovecot
Error: Error in configuration file /etc/dovecot/etc/dovecot.conf line

962: Unknown setting: mail_uid Fatal: Invalid configuration in /etc/dovecot/etc/dovecot.conf

# sbin/dovecot --version
1.2.10

i try, but i dont know how to fix them :(

thanks in advance! :)

-- Salu2 ;)