I don’t know what specific client did you have in mind. Jabber is a name for technology/standard (another name - XMPP). That’s why i said that all jabber clients (meaning using jabber standards) can connect with Openfire. If you mean some specific “Jabber” client, then i’m not aware of it. Probably this is some custom Cisco client they use with their Cisco Jabber server (former Jabber XCP). If they haven’t deviated from jabber standards it should in theory work with Openfire or any other jabber server. Unless you mean Openfire server interconnecting with Cisco Jabber server. Then it again depends on what Cisco have changed/removed in their server. In theory it should support standard jabber server-to-server connection and then Openfire would connect with Cisco Jabber server and users from one server should be able to communicate with another server’s users. So i think you should clarify what exactly (client or server) you want to integrate with.
The easiest way would be to setup Openfire and try logging in with Jabber client, etc. Openfire setup is very simple and you can use embedded database for testing.