[SR-Users] Getting "uac.reg_add" to work (documentation unclarities)

Hello, I am trying to make UAC register with a SIP telco. But when I run... shell$ kamctl rpc uac.reg_add mydomain.com 0123456789 myteldomain.com 0123456789 sip6.telco.nl telcoreseller.nl 999999 secretpw . udp:sip6.telco.nl 360 0 10 'udp:[fd8:9::10]:5090' ...it gives me the cryptic response... ERROR: jsonrpcs [jsonrpcs_mod.c:666]: jsonrpc_scan(): field is not a string - type 3 The module docs only give "..." as example of attributes. And, according to... http://www.kamailio.net/docs/modules/5.4.x/modules/uac.html#uac.r.uac.reg_a… https://github.com/kamailio/kamailio/blob/5.4.4/src/modules/uac/uac_reg.c#1… ...it also seems to be behind on diff_expires, timer_expires, reg_init. What I am missing is the format, and in some cases the purpose of attributes. Could you help me to an example, perhaps based on the command I am trying? Thanks, -Rick P.S. It's been years since I worked with OpenSIPS. It feels like Kamailio is friendlier, and easier to use.