ReserveGroup Reservevalue

Hi,
Would like to know if the below message flow is valid scenarios for
IPV6 and IPV4 connection with ReserveGroup= true.


MGC-->MG
"      Add = DS0/1/1;
        Add = $ {
                Media {
                        LocalControl {
                                Mode = ReceiveOnly,
                                ReserveGroup = true,
                                ReserveValue = true}
                         Local {
 v=0
 c=IN IP4 $
 m=audio $ RTP/AVP 4
 m=audio $ RTP/AVP 0  ; IP termination for audio
  m=image $ udptl t38
                        ;IP termination for fax
 v=0
c=IN IP6 $
 m=image $ udptl t38
                        ;IP termination for fax
"


MG--->MGC:
"
Context = 2000 {
      Add = DS0/1/1;
       Add = RTP/1 {
               Media {
                        Local {
 v=0
 c=IN IP4 124.124.124.222
 m=audio 2222 RTP/AVP 4
 m=audio 2222 RTP/AVP 0  ;
 m=image $ udptl t38
                        ;IP termination for fax All values are possible
v=0
 c=IN IP6 0.0.0.0        ; not active
 m=image 1111 udptl t38   ;other udp port for fax
 a=...                  ;
}"


Thanks,
Sharada