asterisk users - Aug 2007 - flash zap FXO port from SIP device (SPA-2002) using RFC2833 or SIP INFO

Sorry if this was posted yesterday, I was having issues with being 
auto-unsubscribed because of my spam filter. Not sure if my post made it 
   through.

Hi everyone,

I'm wondering if I'm missing something obvious here, or if Asterisk just
doesn't support what I'm trying to do. It seems like it should be 
simple, but appearances can be deceiving.

I've got an Asterisk box and an SPA-2002, the Asterisk box has a TDM400P 
populated with FXO ports.

The Asterisk box is attached to the station (FXS) ports of a traditional 
analog PBX, as you might imagine it uses flash to access features like 
transfer.

I want to be able to flash the FXS port of the SPA-2002 and have that 
flash propagate to the corresponding FXO port (on the TDM-400P).

After you disable the various features of the SPA-2002 that require 
flash, it can then send flash as either an RFC2833 or SIP INFO event 
rather than handling it internally.

How do I get Asterisk to act on one of those two events and flash the 
FXO end?

This seems to be exactly what I'm trying to do:
http://bugs.digium.com/view.php?id=4283&nbn=8

setting "Flash TX method" to SIP INFO.

<--- SIP read from 192.168.4.98:5060 --->
INFO sip:9 at 192.168.4.12 SIP/2.0
Via: SIP/2.0/UDP 192.168.4.98:5060;branch=z9hG4bK-34d6f914
From: spa1l1 <sip:spa1l1 at 192.168.4.12>;tag=27e0074d58f7a49ao0
To: <sip:9 at 192.168.4.12>;tag=as7da5d155
Call-ID: 2b9ec789-867f818e at 192.168.4.98
CSeq: 103 INFO
Max-Forwards: 70
Proxy-Authorization: Digest 
username="spa1l1",realm="asterisk",nonce="7a6afc99",uri="sip:9
at
192.168.4.12",algorithm=MD5,response="5488f11b8ec0bf6298dc70ffd79559c7"
User-Agent: Linksys/SPA2002-3.1.20
Content-Length: 11
Content-Type: application/hook-flash

Signal=hf

<------------->
--- (11 headers 1 lines) ---
Receiving INFO!
[Aug 18 21:28:48] WARNING[13157]: chan_sip.c:10977 handle_request_info: 
Unable to parse INFO message from 2b9ec789-867f818e at 192.168.4.98. Content

The above seems strange to me, that there is nothing after the word 
Content in the warning. Seems like there should be "hf" there.

using RFC2833 (AVT) and application/hook-flash shows nothing on console 
using sip debug and doesn't work.

using RFC2833 (AVT) and application/dtmf-relay does the same as above.

Mike