+**Important compatibility information:**
+If older Fhem-versions (before 2015-06-19) or other software ([Homegear][],
+[LXCCU][], a real [CCU][], Windows configuration software, ...) is used
+to connect to hmland, the `-I` switch might be needed to impersonate a
+LAN-interface (this replaces the identity string HM-USB-IF with HM-LAN-IF).
+Software which needs this will not keep a stable connection open to
+hmland without this switch. It was the hardcoded default in versions
+< 0.100.
+
+This incompatibility is needed so connecting software is able to
+differentiate between HM-CFG-LAN and HM-CFG-USB.
+
+[releases-directory]: https://git.zerfleddert.de/hmcfgusb/releases/