[CentOS] best way something thinks to upgrade dovecot to 1.2.* 2.0.* via atrpms, atrpms-testing

hello all
hello centos network

What are your tips for successful migration for dovecot (atrpms , 
atrpms-testing depot )
the page of wiki
http://wiki2.dovecot.org/Upgrading/2.0
explains the method to upgrade

I tried on my personal machine and the command cites wiki returns 
errors on the terminal
what to do with errors: correct the error in the configuration file ?


many returns are welcome
something thinks are welcome

thanks