Cisco ISR received: SIP/2.0 400 Bad Request - Malformed..

I have an internal customer with an iPhone trying to forward all calls to their desk phone.  Calling his phone directly works just fine.  But when forwarding all from his AT&T iPhone ccsip messages debug at the 3845 ISR outputs in part what I've posted below (altered to protect the innocent.)  Any IP Telephony hotshots on here to lend insight as to what's going on?

INVITE sip:9164896045@57.22.34.234:5060 SIP/2.0
Via: SIP/2.0/UDP 27.15.69.99:5060;branch=z9hG4bK02B4b323079bc2e4e47
From: <sip:7774440500@27.15.69.99:5060;pstn-params=9084818088>;tag=gK02581260
To: <sip:9164896045@57.22.34.234:5060>
Call-ID: 453134832_44257581@27.15.69.99
CSeq: 32276 INVITE
Max-Forwards: 29
Allow: INVITE,ACK,CANCEL,BYE,REGISTER,REFER,INFO,SUBSCRIBE,NOTIFY,PRACK,UPDATE,OPTIONS,MESSAGE,PUBLISH
Accept: application/sdp, application/isup, application/dtmf, application/dtmf-relay,  multipart/mixed
Contact: <sip:7774440500@27.15.69.99:5060>
P-Preferred-Identity: <sip:7774440500@27.15.69.99:5060>
Diversion: <sip:27.15.69.99:5060>;privacy=off;screen=no; reason=unconditional; counter=1
Diversion: <sip:27.15.69.99:5060>;privacy=off;screen=no; reason=unconditional; counter=1
Supported: timer,100rel
Session-Expires: 1800
Min-SE: 90
Content-Length:  235
Content-Disposition: session; handling=required
Content-Type: application/sdp

v=0
o=Sonus_UAC 24402 0 IN IP4 27.15.69.99
s=SIP Media Capabilities
c=IN IP4 27.15.69.74
t=0 0
m=audio 8164 RTP/AVP 0 101
a=rtpmap:0 PCMU/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15
a=sendrecv
a=maxptime:20

16885682: Mar 14 09:26:12.586 PDT: //-1/xxxxxxxxxxxx/SIP/Msg/ccsipDisplayMsg:
Sent:
SIP/2.0 400 Bad Request - 'Malformed CC-Diversion/Diversion/CC-Redirect Header'
Via: SIP/2.0/UDP 27.15.69.99:5060;branch=z9hG4bK02B4b323079bc2e4e47
From: <sip:7774440500@27.15.69.99:5060;pstn-params=9084818088>;tag=gK02581260
To: <sip:9164896045@57.22.34.234:5060>;tag=C81A6E14-C2C
Call-ID: 453134832_44257581@27.15.69.99
CSeq: 32276 INVITE
Reason: Q.850;cause=100
Content-Length: 0