[OpenSIPS-Users] perl_exec parameter variable issue

[Admin]

Hi,
 When passing a variable to perl_exec as a parameter, i received a
parsing error in the opensips log and won't start. Here is what I am
doing inside the opensips config. file

$var(duration) = $DLG_lifetime;
perl_exec("update_user_balance", $var(duration));

It seems that it wants the parameter in quotes ("$var(duration)") but i
don't get the variable value when i pass it in quotes. 

There was a similar problem posted in the archives but no solution was
presented. 

Any suggestion on how to work this around is very appreciated. May be
something similar to dialogue lifetime from the OPENSIPS Perl API.

I am running OpenSIPS (2.1.0 (x86_64/linux)).

Thanks.