answering to myself, the solution is to assign integer value to
$var(name). test
$var(name) = 1000;
$avp($var(name)) = "value";
xlog("L_INFO", "avp i:1000 has value <$avp(i:1000)>\n");
xlog("L_INFO", "avp s:i1000 has value <$avp(s:i:1000)>\n");
produces to syslog
Nov 8 13:26:25 sip /usr/sbin/sip-proxy[8980]: INFO: avp i:1000 has value <value>
Nov 8 13:26:25 sip /usr/sbin/sip-proxy[8980]: INFO: avp s:i1000 has value
<<null>>
i didn't find this documented anywhere. should it be added to pv wiki
page or is it too obvious?
-- juha