Sender variable must be initialised

May or may not be a bug/issue. Thoughts?

type hexstring MACAddress length(12) with { variant "BYTEORDER(first),HEXORDER(high)"};

... in test code ...

var MACAddress v_sutMAC;
var RespType v_resp;
pt_someport.send(someTemplate) -> value v_resp sender v_sutMAC { ... }

Results in error "Initialization from an unbound hexstring value."

Initialising v_sutMAC := '000000000000'H, removes the error.

Should an out value like sender require a bound variable?