Flash softphone in openfire

HI everybody:
Recntly,We are doing some work about flash softphone in openfire.
The flash voip client is based on red5phone(Do not use spark),and our plan is red5phone + openfire + asterisk .
We have little experience on the project before, After looking up for forum discussion we try to draw the framework picture,but some misunderstanding must be here:
http://img.ph.126.net/mWDMPwicsFlxiwiJuq7rfw==/3341952398486311575.jpg

some issue below:
1.About plugin. We think that openfire should involve red5 plugin, sip phone plugin and asterisk-IM plugin, If any else is missing or not necessary, do me a favor, point out.
2.About asterisk-IM plugin. If asterisk-IM plugin is necessary, Would you like to tell me how the plugin works and what’s the ‘?’ on the picture?
any suggestion will be most appreciated.

help!

look here please