Hi, I want to limit the simultaneous calls on my Openser server. I use this code to limit the calls: ..... isten=xxx.xxx.xxx.xxx listen=xxx.xxx.xxx.xxx. # put your server IP address here port=5060 children=4 dns=no rev_dns=no fifo="/tmp/openser_fifo" fifo_db_url="mysql://xxxxxxxxxxxxxx loadmodule "/usr/lib/openser/modules/mysql.so" loadmodule "/usr/lib/openser/modules/sl.so" loadmodule "/usr/lib/openser/modules/tm.so" loadmodule "/usr/lib/openser/modules/rr.so" loadmodule "/usr/lib/openser/modules/maxfwd.so" loadmodule "/usr/lib/openser/modules/usrloc.so" loadmodule "/usr/lib/openser/modules/registrar.so" loadmodule "/usr/lib/openser/modules/uri_db.so" loadmodule "/usr/lib/openser/modules/auth.so" loadmodule "/usr/lib/openser/modules/auth_db.so" loadmodule "/usr/lib/openser/modules/uri.so" loadmodule "/usr/lib/openser/modules/domain.so" loadmodule "/usr/lib/openser/modules/textops.so" loadmodule "/usr/lib/openser/modules/avpops.so" loadmodule "/usr/lib/openser/modules/xlog.so" loadmodule "/usr/lib/openser/modules/dispatcher.so" loadmodule "/usr/lib/openser/modules/permissions.so" loadmodule "/usr/lib/openser/modules/acc.so" loadmodule "/usr/lib/openser/modules/dialog.so" modparam("dispatcher", "list_file", "/etc/openser/dispatcher.list") modparam("acc|auth_db|uri_db|usrloc|permissions", "db_url", "mysql://xxxxxxxxxxx") modparam("avpops","db_url","mysql://xxxxxxxxxxxxxxxx) modparam("auth_db", "calculate_ha1", 1) modparam("auth_db", "password_column", "password") modparam("usrloc", "db_mode", 2) modparam("rr", "enable_full_lr", 1) modparam("tm", "wt_timer", 30) modparam("tm", "fr_timer", 2) modparam("tm", "fr_inv_timer", 120) #modparam("tm", "fr_inv_timer_avp", "inv_timeout") modparam("permissions", "default_allow_file", "/etc/openser/permissions.allow") modparam("permissions", "db_mode", 1) modparam("dispatcher", "flags", 2 ) modparam("acc", "db_flag", 1) modparam("acc", "db_missed_flag", 2) modparam("acc", "log_flag", 1) modparam("acc", "log_missed_flag", 2) modparam("dispatcher", "cnt_avp_id", 4) modparam("avpops","avp_table","gw_avail_port") modparam("dialog", "enable_stats", 1) modparam("dialog","dlg_flag",3) ..... if (avp_check("$DLG_count", "gt/i:10")) { sl_send_reply("403","no more calls accepted"); exit; } But I get the following error when I try to call and it doesn't work: 8(4826) xl_get_spec_value: error - null sp->itf 8(4826) ERROR:avpops:ops_check_avp: cannot get src value My Openser version is 1.1.1 Thanks