Another newbie question, if I may: (I realise this may be more of a modesl/node-esl question than an ESL question per se.) I'm using node-esl/modesl for ESL outbound actions, and can't figure out how to get it to append a custom SIP header on the B leg. Were it the case that the 'set' formula were the same as with most conventional variables, set via a 'params' tag attribute, it'd be easy: conn.execute('set', 'foo=bar'); However, in the case of the ${sip_h...} container, this is specified as the body value of the <action> tag, not a 'params' attribute. Example per http://wiki.freeswitch.org/wiki/Sofia-SIP#Adding_Custom_Headers: <action application="set"><![CDATA[sip_h_P-Charge-Info=<sip:${caller_id_number}@${domain_name}>;npi=0;noa=3]]></action> I can't quite figure out how to get the API to mimic this effect. The second argument to the execute() method appears to get turned into tag attributes only. From https://github.com/englercj/node-esl/blob/master/lib/esl/connection.js: Connection.prototype.execute = function(app, arg, uuid, cb) { ... opts['execute-app-name'] = app; opts['execute-app-arg'] = arg; ... Am I just SOL on that one? I suppose one option is to run the call through a loopback endpoint that takes care of the header-setting in dialplan XML, but, as the aim is to build a thoroughly API-controlled environment, I'd rather avoid that kludge if I can help it. Any insights appreciated! -- Alex -- Alex Balashov - Principal Evariste Systems LLC 235 E Ponce de Leon Ave Suite 106 Decatur, GA 30030 United States Tel: +1-678-954-0670 Web: http://www.evaristesys.com/, http://www.alexbalashov.com/