From Claws Mail FAQ
Claws Mail Development Model
Stage 0: Propose ideas/goals Stage 1: Some bug fixing Stage 2: Implementation, single developer testing and committing to CVS Stage 3: Synchronization and multiple developer (and CVS users) testing, unless the code is mature enough, go to 1 or 2 (or even 0). From time to time, migrate bugfixes to stable branch. Stage 4: Depending on the goals reached, code maturity, moon phase and other variables, release a stable bugfix, a beta, or a rc. Stage 5: Magic happens here. Stage 6: Feature freeze (usually 2 weeks before 8). Stage 7: String freeze (usually 1 week before 8). Stage 8: Release a new shiny version.
Motto: All of this can change at developers will. Code must flow.