[SR-Users] xlog/xdbg syntax

Hi All, Using Kamailio 4.0.0 with a minimal configuration, trying to get some logging to help me understand the system, I can get static log messages easily enough with log, but now want something more useful. When I use this route (xdbg example from the tutorial): route { xdbg("SIP Request: method [$rm] from [$fu] to [$tu]\n"); } the log file shows these messages: DEBUG: <core> [sr_module.c:935]: DEBUG: init_mod: xlog DEBUG: <core> [main.c:2539]: Expect (at least) 13 SER processes in your process list DEBUG: <core> [route.c:927]: fixing xdbg() DEBUG: <core> [pvapi.c:390]: PV <$rm> is not in cache DEBUG: <core> [pvapi.c:269]: PV cache not initialized, doing it now ERROR: <core> [pvapi.c:761]: error searching pvar "rm" ERROR: <core> [pvapi.c:965]: wrong char [m/109] in [$rm] at [2 (0)] ERROR: xlog [xlog.c:363]: wrong format[SIP Request: method [$rm] from [$fu] to [$tu]#012] and Kamailio shuts down. Have I missed something obvious? Cheers, Dave.