Kamailio5.5.4

$var(s) = "a=1;b=2;c=3";

$var(s1) = $(var(s){param.value,b}); // work well

$var(s) = "a=1|b=2|c=3";

$var(s1) = $(var(s){param.value,b,|}); // work well

// but

$var(s) = "a=1,b=2,c=3";

$var(s1) = $(var(s){param.value,b,,});

ERROR: <core> [core/pvapi.c:1131]: pv_parse_spec2(): invalid parsing in [$(var(s){param.value,b,,})] at (4)

CRITICAL: <core> [core/cfg.y:3683]: yyerror_at(): parse error in config file /etc/kamailio/kamailio.cfg, line 366, column 13-38: Can't get from cache: $(var(s){param.value,b,,})