CAS SingleSignOutFilter problems

[Steve Podell]

CAS is working great for our webapps.  I need to add single signout to 
our setup to do some cleanup in the soon to be invalidated sessions on 
logout.  So I added the Single Sign out filter and listener as described 
here...
http://www.ja-sig.org/wiki/display/CASC/Configuring+Single+Sign+Out

I am using cas-server-core-3.1.jar

When I set a debugger breakpoint in 
org.jasig.cas.client.session.SingleSignOutFilter, I can see requests 
coming through, but I never see a POST, so the request parameter 
"logoutRequest" is not acted on. I also don't see the 
artifactParameterName/"ticket" parameter coming through either, so the 
the session references are not being cached.

The wiki page
http://www.ja-sig.org/wiki/display/CASUM/Single+Sign+Out
mentions an ArgumentExtractor property called disableSingleSignOut, but 
I don't see where you would set it (and have not set it).

When I watch the requests on a http analyzer on my PC, there is an early 
POST on the login to cas that does contain the ticket on the response. 
But a client side filter would not see the response...?

-  Process : firefox.exe[2748] 
(COUNT=25)                                                                                                                                                                                                                                                                                                                                                

   8     13:03:14:453  0.264 s      POST    302     0     text/plain 
https:///iii/cas/login;jsessionid=3C16428223AD4231E9079B8B50804C19?service=https%3A%2F%2Fmtdemo.iii.com%3A443%2Fiii%2Fmfrpro%2Fj_acegi_cas_security_check 

https://mtdemo.iii.com:443/iii/mfrpro/j_acegi_cas_security_check?ticket=ST-5-SfMWDEiDcVLVoLxsaEbYfcT3ZXTupEvGHHB-20

So some basic questions:
1) This filter is client side cache of tickets and sessions?
2) I should be seeing logoutRequest POSTs to the webapp so that the CAS 
client code can cache the tickets?
3) I should be seeing POSTs with "ticket" as a request parameter?
4) This feature is in cas-server-core-3.1?
5) The feature defaults to "on"? The ArgumentExtractor properties are 
already set up?