The program is
remotePROTECT
http://scpsoft.com/remoteprotect.htm
It's not really dangerous, I mean you're not sending some random SMS message but rather one with a special flag (namely your pass code), so not sure why people think that. For people with sensitive information, government jobs, etc. it's actually very valuable software and many use it.
Anyways, it has received raving reviews from users and it plays nice with WM5, even with the Treo 700wx and I'd imagine the 6700.