Paul, I know, ecryptfs mount should not end in infinite loop, but don't take this as workaround. The verbosity=0 is needed here. Infinite loop is fixed, but without verbosity=0 mount helper will ask you (or cron) for missing values. If you (cron) enter invalid values it'll ask again (5 times at most - this is new). After that it'll fail with 'invalid value' error.