I think no module needed just a properly configured powerdns. Which linux distribution are you using? I will do powerdns setup on gentoo.
Powerdns uses a different table structure then mydns and as far as I know you can not specify the sql queries in the powerdns configuration so falko has written a wrapper plugin for ispconfig. There is a powerdns plugin in SVN, but you have to enable it manually.
You CAN specify the querys in powerdns. http://downloads.powerdns.com/documentation/html/generic-mypgsql-backends.html#AEN5649 But first I will check the module. BTW, do mydns do NOTIFY to the slaves?
Is there any rule howto prompt the user to make selection in the install between for example powerdns and mydns? I can hack the install to configure powerdns instead of mydns, but I was wandering if there is a nicer solution...