sip-router writes:
Details - There is an annoying difference between an
uninitialized
$avp and $var. When the value is queried, the $avp returns <null>
whereas the $var returns 0. The latter is wrong, as 0 is a meaningful
value.
this has been discussed before. check archives. if i remember
correctly, vars are implemented in such a way that it is not possible to
differentiate 0 from null.
-- juha