[Serusers] radius accounting, duplicate rows and missing columns

I've this ser installation whose purpose in life is accounting all the calls and redirecting them to asterisk, which routes them to ISDN or a h323 GSM gateway. SIP phones -> Ser -> Asterisk -> [isdn | gsm ] all the calls are "from left to right", asterisk will never see incoming stuff from the isdn/gsm channels radius has mysql as backend, the calls works well but : if the sip phone hangsup radius writes two identical lines in the radacct table, missing the AcctSessionTime value (writes '0') if the remote phone hangsup there are the same two lines and a third line with caller and called inverted, and start and stop time with the same value Can someone tell me what's wrong with my route ? or I'm missing something in radius configuration ? some columns and lines from the radacct table "RadAcctId","AcctSessionId","AcctUniqueId","UserName","AcctStartTime","AcctStopTime" #these lines inserted if the caller hangsup first 49,"e7e71b1b-70eec1ee(a)172.18.1.13","d9428a25afbfdf52","[sip number]","2005-08-10 08:54:53","2005-08-10 08:54:58" 50,"e7e71b1b-70eec1ee(a)172.18.1.13","d9428a25afbfdf52","[sip number]","2005-08-10 08:54:53","2005-08-10 08:54:58" #these if the called number hangsup 51,"72660925-e480d1a5(a)172.18.1.13","43e7c757d53c2970","[sip number]","2005-08-10 08:57:10","2005-08-10 08:57:22" 52,"72660925-e480d1a5(a)172.18.1.13","43e7c757d53c2970","[sip number]","2005-08-10 08:57:10","2005-08-10 08:57:22" 53,"72660925-e480d1a5(a)172.18.1.13","5b732c77e7e3f37d","[external number]","2005-08-10 08:57:13","2005-08-10 08:57:13" acc_radius paramethers : modparam("acc", "radius_config", "/etc/radiusclient-ng/radiusclient.conf") modparam("acc", "log_level", 2) modparam("acc", "log_fmt", "cdfimorstup") modparam("acc", "radius_flag", 1) routing configuration : # initial sanity checks if (!mf_process_maxfwd_header("10")) { sl_send_reply("483","Too Many Hops"); break; }; if ( msg:len > max_len ) { sl_send_reply("513", "Message too big"); break; }; # registration (and authentication) if (uri==myself) { if (method=="REGISTER") { if (!radius_www_authorize("")) { www_challenge("", "0"); break; }; save("location"); break; }; lookup("aliases"); }; setflag(1); if (method=="INVITE") record_route(); rewritehost("172.18.1.11"); if (!t_relay()) { sl_reply_error(); };