Electronic Alarms and Home Security Devices - Motion detection for sun room

I have a sun room with windows on three sides and skylights on the ceiling. I'm looking for a motion detector that will work in that environment.

Since most PIR's caution against facing a window, that leaves me with a problem of where to mount one of those, is there any other technology that might be more appropriate? I know there used to be ultrasonic motion detectors, but I don't see many of those when I look around. RF detectors also seem to be an option, though I've been told those can detect movement outside the structure. Since we have a large deer population, that might be a problem.

I'm also considering a glass break detector as an alternative (discussed in another thread), I'm looking for something with minimal false alarm possibility that will be reliable.

The problem with motions in sunrooms is a thing called "hot spotting". It's where the sun works its way around to a point on the horizon where there is suddenly a bright spot of light coming through a window. It tends to be seasonal, there are usually a couple of weeks a year when it happens, depending on the orientation of the room.

One trick is to use two motions mounted with overlapping views, and wired in parallel (instead of the normal series) so that both devices have to be triggered simultaneously.

You can also go with the dual tech motions that have to agree on a trip from both a microwave sensor _and_ the infrared sensor.