Anyway, a better idea is upgrading to 1.0; dovecot 0.99 is really old and no longer supported.
:-\ I use the version including in my SL 4.4 distribution I hope there's some RPM somewhere for the 1.0
WARNING!Be sure to read the update notes - the config file format has changed between 0.99 and 1.0.0...
http://wiki.dovecot.org/UpgradingDovecot -- Best regards, Charles