mail server setting

Please set mail server on my hosting. I am using VPS in Korea. and ubuntu 11.10. It was well operated in the past. but now I changed apache mpm mode from prefork to worker. and use php5-fpm. but now mail sending is not working. and i want to set dovecot with squirrel mail. please fix this problem on my server. but you need to connect to my laptop through vnc sharing or teamviewer. plz add {Removed by Admin} <--- s ky ... pe {Removed by Admin} <-- g m ...a il