415 Unsupported Media Type

dear sir
I configured my system to send MESSAGES between two softphones and I can send text messages, now I want to be able to send images from one to other, on the softphone I attached image and send it however I got error 415 Unsupported Media Type
here is my dial plan

[astsms]
exten => _00962XXXXXXXXX,1,NoOp(SMS receiving dialplan invoked)
exten => _00962XXXXXXXXX,n,NoOp(To ${MESSAGE(to)})
exten => _00962XXXXXXXXX,n,NoOp(From ${MESSAGE(from)})
exten => _00962XXXXXXXXX,n,NoOp(Body ${MESSAGE(body)})
exten => _00962XXXXXXXXX,n,Set(ACTUALTO=${CUT(MESSAGE(to),@,1)})
exten => _00962XXXXXXXXX,n,Set(ACTUALFROM=${CUT(MESSAGE(from),@,1)}) 
exten => _00962XXXXXXXXX,n,MessageSend(${ACTUALTO},${MESSAGE(from)})
exten => _00962XXXXXXXXX,n,NoOp(Send status is ${MESSAGE_SEND_STATUS})
exten => _00962XXXXXXXXX,n,GotoIf($["${MESSAGE_SEND_STATUS}" != "SUCCESS"]?sendfailedmsg)
exten => _00962XXXXXXXXX,n,Hangup()

; Handle failed messaging

;exten => _00962XXXXXXXXX,n(sendfailedmsg),Set(MESSAGE(body)="[${STRFTIME(${EPOCH},,%d%m%Y-%H:%M:%S)}] Your message to ${EXTEN} has failed. Retry later.")
;exten => _00962XXXXXXXXX,n,Set(ME_1=${CUT(MESSAGE(from),<,2)})
;exten => _00962XXXXXXXXX,n,Set(ACTUALFROM=${CUT(ME_1,@,1)})
;exten => _00962XXXXXXXXX,n,MessageSend(${ACTUALFROM},ServiceCenter)
exten => _00962XXXXXXXXX,n,Hangup()
exten => _00962XXXXXXXXX,n,Hangup() 

and here what I got in SIP debug

<--- SIP read from UDP:10.225.47.209:55061 --->
MESSAGE sip:00962795255249@xxxxxxxxxxxx SIP/2.0
Via: SIP/2.0/UDP 10.225.47.209:55061;branch=z9hG4bK.o56GiC2Ci;rport
From: <sip:00962795255248@xxxxxxxxxxxx>;tag=5kt-LfMXE
To: sip:00962795255249@xxxxxxxxxxxx
CSeq: 20 MESSAGE
Call-ID: OfXYc-RvO-
Max-Forwards: 70
Supported: outbound
Content-Type: application/vnd.gsma.rcs-ft-http+xml
Content-Length: 377
Date: Tue, 22 Sep 2015 12:24:33 GMT
User-Agent: LinphoneIphone/2.3 (belle-sip/1.4.1)

<?xml version="1.0" encoding="UTF-8"?><file xmlns="urn:gsma:params:xml:ns:rcs:rcs:fthttp">
<file-info type="file">
<file-size>81416</file-size>
<file-name>94426128-464617468.020497.jpg</file-name>
<content-type>image/jpeg</content-type>
<data url = "https://www.linphone.org:444//tmp/56014881da4a5_8957f3d397bfd33d1c88.jpg" until = "2015-09-29T12:24:33Z"/>
</file-info>
</file>
<------------->
--- (12 headers 8 lines) ---
Sending to 10.225.47.209:55061 (NAT)
Receiving message!

<--- Transmitting (NAT) to 10.225.47.209:55061 --->
SIP/2.0 415 Unsupported Media Type
Via: SIP/2.0/UDP 10.225.47.209:55061;branch=z9hG4bK.o56GiC2Ci;received=10.225.47.209;rport=55061
From: <sip:00962795255248@xxxxxxxxxxxx>;tag=5kt-LfMXE
To: sip:00962795255249@xxxxxxxxxxxx;tag=as565e6f25
Call-ID: OfXYc-RvO-
CSeq: 20 MESSAGE
Server: FPBX-AsteriskNOW-12.0.76.1(11.16.0)
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH, MESSAGE
Supported: replaces, timer
Content-Length: 0


<------------>
Scheduling destruction of SIP dialog 'OfXYc-RvO-' in 32000 ms (Method: MESSAGE)

This is not supported.

Dear Sir
so what is my alternatives??

As Asterisk does not support the provided content type you would have to use something else. What that would be I don’t know, as it depends on what exactly you are trying to achieve overall.