I've just released a new Windows application (it should run under Wine on Linux too) that allows you to connect and communicate with many remote serial terminals connected to XBee clients, all at the same time with a single basestation coordinator.
I've ironed out most of the issues so far with the current release, and it has most features you should find useful.
I'm just wondering if there's any additional features or changes you would like to see in an application like this, or if you come across any issues. I'm hoping to get a comprehensive list of supported hardware configurations. So if you test it out, it would help immensely to report it working in the GitHub wiki supported hardware page.