Comment 8 for bug 1449282

Robert, the following snippet is used to retrieve current Xorg version in http://bazaar.launchpad.net/~ltsp-upstream/ltsp/ldm-trunk/view/head:/screen.d/ldm:

X -version 2>&1 | grep "X.Org X Server" | sed -n 's/X.Org X Server //p'

Maybe you can use it in a new function e.g. x_server_local_minimal_version (major, minor, bgufix):

if x_server_local_minimal_version (1, 17, 0) {
    // Do stuff for Xorg server >= 1.17.0
}