I have Openfire running on a server and i have configured some Empathy clients on Ubuntu 9.10, some iChat clients on Mac OSX and a lot of Spark clients on Windows.
Spark play well between Windows clients but when i want to tranfer a file between Spark Windows and Ichat on Mac OSX or Empathy on Ubuntu 9.10. It does’nt work ! But between iChat and Empathy, it works ???
Then, i have installed Spark on Mac OSX and Ubuntu 9.10 and it works !
But on Ubuntu 9.10, Computers with Spark 2.6.0 beta 2 are working with some bugs with the tar.gz package but not with the .deb package that requires libstcd++5; Ubuntu 9.10 has libstdc++6 !
The bugs on ubuntu are a double icon on the notification bar and Spark’s windows are not always visible in the task bar !
So, i prefer using empathy that have a great integration on the system but the file transfer is not working !
I suggest to watch this doc http://www.igniterealtime.org/community/docs/DOC-1822 and wait for the updated deb package. Or you can use jar installer instead. I havent see the bugs that you described with the latest version on Ubuntu. As about file transfer problems, there are alot more problems with transfers, and there are no developers to fix that.
Sorry, but i’m unable to reproduce both double-icon and message window doesnt appearing in the bottm taskbar issue on my Ubuntu 9.10 in VirtualBox with the Spark jar installer.