How to make VPN on Demand work on iOS7

Help would be much appreciated on how making VPN on Demand working on iOS7.

1) Is it true that VPN on Demand only work if your target domain doesn't exist in public DNS? I found that it is the difference between iOS6 and iOS7.

2) For iOS7, i tried something suggested in the following site (http://stackoverflow.com/questions/18948253/setting-up-a-vpn-configuration-profi le-on-ios-7) and it doesn't work.

<key>IPSec</key>
<dict>
    <key>AuthenticationMethod</key>
    <string>Certificate</string>
    <!-- Other IPSEC VPN properties here. -->
    <key>OnDemandEnabled</key>
    <integer>1</integer>
    <key>OnDemandRules</key>
    <array>
        <dict>
        <key>Action</key>
        <string>Connect</string>
        <key>DNSDomainMatch</key>
        <array>
          <string>yahoo.com</string>
        </array>
    </dict>
    </array>
</dict>

Can someone shed some light on it?

Thanks,

-Tam