IdP Proprietary/Simple Logout customization

[Scott Koranda]

Hello,

I would like to invoke the IdP Proprietary/Simple Logout endpoint with a
query string and have a customized template login.vm be able to read the
query string.

I thought that since the template login.vm has access to
HttpServletRequest, this would be straightforward, but what I see is
that when I invoke

/idp/profile/Logout?foo=bar

I receive back a 302 with a redirect to

/idp/profile/Logout?execution=e1s1 

and the template login.vm only "sees" the query string 'execution=e1s1'.

I also explored the flowRequestContext object but it too appears to be
evaluated after the 302 and so I do not have access to the query string
I sent in.

Is there any way to preserve the query string so that the customized
template login.vm has access to it?

Thanks,

Scott K