Here is the latest Spark version from SVN.
Known bugs between 2.6.0 Beta 2 and the latest SVN version:
SPARK-1059 Show a toast popup when "Alert when available" is selected
SPARK-1060 Spark should remember Preferences window (and others) position on the screen
SPARK-1061 Show new messages in systemtray option is not working
SPARK-1062 Improve flashing plugin options
SPARK-1068 Spark is not reacting to outside keyboard events when setting the auto Away status
SPARK-1069 Spark continuos flashing continues to flash after the chat window gets focus
Important to know: in the current SVN version user's profile path has been changed from \Username\Spark to \Username\Application Data\Spark (Windows XP) and \Username\AppData\Roaming\Spark (Windows Vista and 7). ~/.Spark/ ($HOME/.Spark) in Linux.
Installers:
IzPack (11653)
spark-installer.exe.zip
spark-installer.jar
Advanced Installer
spark_2_6_0_11093_online.msi (11093, doesn't have some 11362 build's features or fixes)
spark_2_6_0_11367_online.msi (November 6, 2009 build; SVN revision # 11367)
spark_2_6_0_11427_online.msi (November 27, 2009 build; SVN revision #11427)
spark-noJRE_2.6.0.BETA.20091215.msi (TEST of MSI)
Debian/Ubuntu Packages (11424)
spark_2.6.0_all.deb