Thanks again Sergiu,

Hmmm... if dialog params are wrapped in a ifdef condition, then do you have
something like #!define WITH_DIALOG at the top?

When you do not add #!ifdef WITH_XXX before the parameters and #!endif after, then those parameters will be loaded when starting Kamailio.

So, I still have the issue that the profile is not being loaded.

I have tried renaming the profiles, in the route and the parameters, but that does not make a difference..

# ---- Dialog params -------------
modparam("dialog", "default_timeout", 7200)
modparam("dialog", "db_mode", 0)
modparam("dialog", "dlg_flag", DLG_FLAG)
modparam("dialog", "hash_size", 4096)
#modparam("dialog", "detect_spirals", 1)
modparam("dialog", "profiles_with_value", "inbound ; outbound")

route[CONCURRENT_IN]
{
        #Add call to customer profile
        #Check if customer has not reached inbound call limit

        #Get max concurrent calls
        sql_query("cc", "select max_calls_in from calllimit where cust_id='$avp(custid)'", "ra");
        $avp(maxcalls)=$dbr(ra=>[0,0]);
        sql_result_free("ra");
        $avp(concurrent) = 0;
        get_profile_size("inbound", "$avp(custid)", "$avp(concurrent)");
        if( $avp(concurrent) >= $var(max) )
        {
                xlog("L_INFO"," Call limit reached for customer $avp(custid)\r\n ");
                sl_send_reply("503", "No Lines Available");
                exit;
        }
    set_dlg_profile("inbound", "$avp(custid)");

        return;
}

But this still results in:

Dec  5 09:34:33 proxy01 /usr/local/sbin/kamailio[75755]: CRITICAL: dialog [dialog.c:391]: fixup_profile(): profile <inbound> not defined
Dec  5 09:34:33 proxy01 /usr/local/sbin/kamailio[75755]: ERROR: <core> [core/route.c:1166]: fix_actions(): fixing failed (code=-6) at cfg:/usr/local/etc/kamailio/kamailio.cfg:1578