The client is called DeveloperCompanion and with a pluggable tool called
"FirePHP Companion" it allows interaction with the FirePHP 1.0 server
library. DeveloperCompanion is the best client tool for FirePHP 1.0
going forward.
See:
http://groups.google.com/group/devcomp/browse_thread/thread/2f2a0b01f50a1351
I have put together an example of how to debug an application deployed
to http://orchestra.io/ here:
https://github.com/cadorn/firephp-orchestra
Let me know what you think and please report any issues you are having.
Thanks!
Christoph