Linux VPS Config Script for Multiple IP/Domain PMTA Server

First off please note the server's intended use is as a bulk mail server using PowerMTA as the backend. We handle the heavy pmta's configuration ourselves, but the this setup script must create compatible configurations of server components to our pmta's broad range of controls. The OS will be centos, and script should function equally well on both the 32 and 64 systems. While we have nominal linux experience ourselves, the script we have now achieves only half of what we need below, and we want an experts eyes on a final setup script that can be deployed easily on any linux centos 5/6 system. Assuming the required source files are uploaded, and that proper values are entered in putty, this script should in a single process, provide the following: - Install/config Bind for multiple domains/ip's and multipe smtp servers. At it's minimum, this part should require primary host domain and IP'S for local NS1/NS2, but also needs to take domain/ip's for addon domains. - Setup DKIM Signing, rDNS, PX, MX and SPF records. Run lookups to confirm rDNS. - Remove pre-existing mta's (sendmail,postfix,etc,) and their dependencies. - Install PowerMTA (our copy), but no config necessary. - Install Dovecot. - Install a fully working copy of webmin panel. Setting this up with an alternate port of their default (10000) is fine but IPTABLES must remain active in the final working configuration. Provider must have msn/aol or skype chat to communicate (along with email) and good English. If you want to use one of our VPS's as your sandbox we can accommodate, but script will undergo a final test on a final fresh VPS and all related components will also be overlooked based upon our own PMTA requirements.