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Does it make sense to add a binary compatibility policy? I know that the libs are compatible until KDE 5 but this "Binary compatibility is not required. i18n string changes are allowed" on Schedules/KDE4/4.1_Release_Schedule was confusing until I found "Workspace interface freeze (source and binary compatibility until KDE 4.1)" on Schedules/KDE4/4.0_Release_Schedule. Apparently there are 2 binary compatibility guarantees. One for the libs which lasts over the entire 4 series and one for the workspace which lasts from 4.0 to 4.1 (and presumably then 4.1 to 4.2)