There is a workaround for this.
Do the following in the Polling and Thresholds Console, under Interface Groups:
1) Create a new Interface Group called "PPP interface"
2) Add the following Matching Criteria Type = *PPP*
3) Increase the Priority of this new PPP interface Group to a higher level than the default group Dial on Demand.
4) Reconfigure.
5) Verify that there are now members under the PPP Interface Group.