[Openfire - Webclient] Looking for server to communicate to openfire on port 443/80

After I have found out too late that the SparkWeb needs more ports than port 443, I urgently need another possibility.

Our external users have merely port 80 & port 443 openly.

I need therefore urgently an alternative for a web client who communicates exclusively about one of both ports with Openfire.

I have had a look at some JABBER servers, however, comes on no solution.

It would be fantastic if somebody could help me here in a contemporary way.

Thank you so much,