Bummer... no man for TinyX installed on my system so I used Google to find there really aren't many options for this server.tbh, I don't understand why you would want to disable ctrl+alt+bkspace. It's like taking out ctrl+alt+del.For a remastered DSL into a kiosk of course.
Funny you should mention control+alt+delete because I wanted to strip that out too. What I ended up doing was create a loop script in /usr/bin and called it xlock.
The beauty is, that looping actually kills both ctrl+alt+backspace AND ctrl+alt+delete so win/win for my setup. My end result will be a frugal hard drive install so people can use some aging pc's for Citrix Metaframe access.
original here.