Part of the disco#info xmlns for muc rooms (XEP-0045) allows for additional information discovery besides just "features" and "identities". These are specified by the jabber:x:data xmlns.
I've attached a trial fix that works for muc rooms. It will probably have to be tested more thoroughly in other disco#info situations besides muc. The included zip contains a diff file and my version of InfoDiscoExtension.as.
The attachment has disappeared, is there any chance someone could reattach? Many thanks
Current version of the XEP has the example number 10 containing the relevant data:
Related data also here: