Quoth Sl�vek Banko.....
Because locateLocal expects a TQString value as argument, I suggest using this fact and make the patch simpler:
TDELockFile lock(locateLocal("tmp", "kdesktop_lock_lockfile"));
TDELockFile lock(locateLocal("tmp", TQString("kdesktop_lock_lockfile.%1").arg(getenv("DISPLAY"))));
Thank you Sl�vek, I thought there would be a TDE/TQT way of doing this.
I'll change my in-use version to this.