problem reverse dns

[kiby]

Hello.
I'm using for several days, the control panel ispCP Omega and I am very well. Through the forum I could solve many problems and the documentation has helped me to overcome some obstacles.

My problem is that I have set the reverse DNS to SMTP. How can I do?

I use ubuntu 9.10, ispCP 1.0.6, bind9.

Could someone kindly help to solve the problem?

Thank you in advance.

Sorry for my bad English but I know little