according to this
http://www.piriform.com/docs/defraggler/technical-information/defraggler-and-ssds
Defraggler will use TRIM by default but use zero fill if TRIM is not available.
I'm using Defraggler 2.19 on Windows 7 64 bit and have verified that my system is using TRIM, but when I run "Optimize" , Defraggler says "Optimize operation will zero-fill your drive.... "
Seems like a bug, no?