asterisk users - Jan 2004 - Dial app does not indicate ringing to calling party

I hope somebody has seen this before...

I'm trying to use a Dial command on a inbound call to ring multiple
destinations.    The calls come in to me from the provider on IAX2, and one
of the destinations I try to ring is a IAX2 to call to my cell phone.
When I add the IAX2 destination into the Dial command, the setup I am trying
to achieve works (i.e. my Zap, SIP, and cell phone all ring) but the calling
party does not hear any ringing indication... just dead air until something
answers the call (voicemail or a human).

My IAX2 provider sends me all 10 digits so I have a context set up to catch
it and divert the call to my extension (7000) for handling:

exten => 2065475023,1,SetCIDname(DID 5475023)
exten => 2065475023,2,Goto(stations|7000|1)

Ext 7000 is:
MARK=Zap/2&SIP/mark&IAX2/user@NuFone/1206xxxxxxx
exten => 7000,1,Macro(stdexten,7000,${MARK})

stdext macro:
exten => s,1,Dial(${ARG2}|30|r)
exten => s,2,VoiceMail2(u${ARG1}@stations)
exten => s,3,Hangup
exten => s,102,Voicemail2(b${ARG1}@stations)   ;voicemail busy path
exten => s,103,Hangup

The problem seems to key on the fact that I'm dialing another IAX2
destination during handling of the inbound IAX2 call.   If I dial ext 7000
from inside (SIP or my Zap device) I hear ringing.   If I remove the IAX2
destination from $MARK so that it only tries to ring "local" devices,
it
works.. the calling party hears ringing indication as well.

Is there something I'm missing about IAX2 to IAX2 dialing like this?

Thanks!