I am trying to create an encounter (from admin/encounters/encounter.form) and I chose a visit with incompatible start date for the datetime of the encounter. I try to save, but I only see the error message "Please fix all errors and try again. encounter".
I see a stack trace in my logs indicating the real error:
ERROR - EncounterFormController.onSubmit(208) |2011-12-05 16:20:19,695| Error while trying to save the encounter
org.openmrs.api.APIException: 'Encounter: [(no ID) Mon Dec 05 00:00:00 PST 2011 ADULTINITIAL (no Location) 2 (no Form) num Obs:  num Orders: 0 ]' failed to validate with reason: encounterDatetime: The encounter datetime should be between the visit start and stop dates.
The correct behavior is to show that error message next to the correct field in the form, and to write nothing to the log file.
(I think this error may actually not exist until I do a commit shortly.)