I'd really like to see the acceptance test plan they went through before marketing this thing. If the security sensors came out AFTER the CM15A, okay, perhaps they were a bit reluctant to respin the design and put out a new rev - with a 9.5" longer antenna, or a telescopic one.
The DS10A is quite versatile for various applications, but the CM15A needs to be able to "hear" it, else everything is a non-starter.
I thought for $49 (or was it $59?) I had a great opportunity to try out some basic HA without my wife noticing :-)
I will try the antenna extension. If that doesn't work I may have to look into Homeseer and a 3rd-party 310 MHz receiver.