I won't attempt to navigate your bug reporting system, but I thought you would like to know of several problems I encountered when setting up SIP Communicator on a Ubuntu Karmic system. I'll be happy to answer specific questions and supply logs, but I don't have time for any extended debugging.
The computer is new enough and fast enough. It's an Intel Core 2 Duo, with 1 GB memory, and an almost new and empty system.
1. Ubuntu almost requires a public key for the package, although it can be overridden. This is your bug 787.
2. Installation of SIP Communicator from the package on your Web site damaged my system. It appears to have attempted to install Java over an already installed program. In doing so it opened an unresponsive dialog in Terminal that had to be terminated. Fortunately, the system supplied instructions to initiate self repair.
I can supply logs if you are very specific about which logs.
SIP Communicator problems
Default, ALSA devices. I have used it successfully for echo tests to email@example.com. However:
1. Doesn't start incoming sound until several seconds into the call.
2. Program is slow to start, slow to register, and slow to hang up. It may require a minute or two to startup and register. It takes maybe 10-20 seconds to hang up.
3. Program often takes 2 attempts to start. Java shows in the System Monitor, but the UI doesn't appear on the first attempt.
4. Setup UI is broken. Dropdown lists for sound devices do not show the whole string.
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