I recently downloaded and installed the latest version of Eclipse (3.4.0 aka Ganymede) and ran into some issues when trying to get Subclipse (plugin for subversion) up and running.
Initially I was getting the following error message when accessing Windows->Preferences->Team->SVN->SVN Interface dropdown:
JavaHL (JNI) Not Available
When attempting to view a repository via the "SVN Repository Exploring" perspective I got a different error message:
Unable to load default SVN client
I checked and made sure the proper libraries were installed. Note I include hardy-backports in my packages and the version I am installing is higher than the non-backports package:
sudo apt-get install libsvn-java
There is a libsvn-javahl available however it is listed as a "dummy" package.
The package was already there so the issue continues...
There were a number of ways to fix this issue. I chose to set the path to the JavaHL libraries via a command line argument. I accomplished this by setting my Launcher icon for Eclipse to use the command:
/path/to/eclipse -vmargs -Djava.library.path=/usr/lib/jni
An alternative solution is to set the LD_LIBRARY_PATH environment variable to point to the /usr/lib/jni.