comapre against predecessor with external tool fails for checked-outs
Preference uses deprecated API
http://www.vogella.com/articles/EclipsePreferences/article.html
Replace Preferences with new IEclipsePreferences
Clearcase trigger causes ArrayIndexOutOfBoundsException
Compare with external diff tool always uses LATEST instead of selected version
For external diff tools, compare selected versions always uses LATEST instead of selected version
Compare with predecessor puts predecessor on right of compare window