Noam is correct. When my granddaughter tried to turn on our bathroom light a couple of months ago, she broke the push button on the wall switch, making it hard to use. I was out of wall switches, so I ordered a new one from Automated Outlet. When it arrived I installed it and discovered it was soft-start, so I did a swap with our upstairs bedroom (now a storage area) which is rarely used, and used the wall switch from upstairs in the bathroom.
As I said before, X10 needs to beaten with a switch iron for not changing the number on soft-start modules so the poor users could see at a glance what's new and what's old in their module inventory. We aren't mind readers.