It seems like ical4j can’t parse the VTIMEZONE given by Horde. The one bundled with ical4j works.
Do you know if there’s something like a VTIMEZONE validator out there? Do you think it’s possible that the Horde VTIMEZONE is incorrect or that the problem is caused by ical4j and for what reason?
VTIMEZONE given by Horde (can’t be parsed by ical4j 1.0.6):
BEGIN:VTIMEZONE
TZID:America/Montevideo
BEGIN:STANDARD
DTSTART:18980628T000000
TZOFFSETFROM:-0344
TZOFFSETTO:-0344
TZNAME:MMT
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
DTSTART:19231002T000000
TZNAME:UYHST
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
TZNAME:UY-T
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
TZNAME:UYHST
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
DTSTART:19331029T000000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10;UNTIL=19351027T033000Z
TZNAME:UYHST
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
DTSTART:19340331T233000
RRULE:FREQ=YEARLY;BYMONTH=3;BYMONTHDAY=25,26,27,28,29,30,31;BYDAY=1SA;UNTIL
=19360330T030000Z
TZNAME:UY-T
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
DTSTART:19361101T000000
TZNAME:UYHST
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
DTSTART:19370328T000000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=3;UNTIL=19410330T033000Z
TZNAME:UY-T
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
DTSTART:19371031T000000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10;UNTIL=19401027T033000Z
TZNAME:UYHST
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
DTSTART:19410801T000000
TZNAME:UYHST
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0330
TZOFFSETTO:-0330
DTSTART:19420101T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0330
TZOFFSETTO:-0230
DTSTART:19421214T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0300
TZOFFSETTO:-0300
DTSTART:19420101T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19421214T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19430314T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19590524T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19591115T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19600117T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19600306T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19650404T000000
RRULE:FREQ=YEARLY;BYMONTH=4;BYDAY=1SU;UNTIL=19670402T030000Z
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19650926T000000
TZNAME:UY-T
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0300
TZOFFSETTO:-0300
TZNAME:UY-T
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0300
TZOFFSETTO:-0300
TZNAME:UYHST
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0300
TZOFFSETTO:-0300
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19720424T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19720815T000000
TZNAME:UY-T
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-0300
TZOFFSETTO:-0300
DTSTART:19740310T000000
TZNAME:UYHST
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19741222T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19761001T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19771204T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19780401T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19791001T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19800501T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19871214T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19880314T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19881211T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19890312T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19891029T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19900304T000000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=1SU;UNTIL=19920301T030000Z
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:19901021T000000
RRULE:FREQ=YEARLY;BYMONTH=10;BYMONTHDAY=21,22,23,24,25,26,27;BYDAY=1SU;UNTI
L=19911027T030000Z
TZNAME:UYST
END:DAYLIGHT
BEGIN:DAYLIGHT
TZOFFSETFROM:-0200
TZOFFSETTO:-0200
DTSTART:19921018T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:19930228T000000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:20040919T000000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:20050327T020000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:20051009T020000
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:20060312T020000
TZNAME:UY-T
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
DTSTART:20061001T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=1SU
TZNAME:UYST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
DTSTART:20070311T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYMONTHDAY=8,9,10,11,12,13,14;BYDAY=1SU
TZNAME:UY-T
END:STANDARD
END:VTIMEZONE
VTIMEZONE bundled by ical4j 1.0.6:
BEGIN:VTIMEZONE
TZID:America/Montevideo
TZURL:http://tzurl.org/zoneinfo/America/Montevideo
X-LIC-LOCATION:America/Montevideo
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
TZNAME:UYST
DTSTART:20061001T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=1SU
X-RADICALE-NAME:America/Montevideo
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
TZNAME:UYT
DTSTART:20070311T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU
X-RADICALE-NAME:America/Montevideo
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-034444
TZOFFSETTO:-034444
TZNAME:MMT
DTSTART:18980628T000000
RDATE:18980628T000000
X-RADICALE-NAME:America/Montevideo
END:STANDARD
BEGIN:STANDARD
TZOFFSETFROM:-034444
TZOFFSETTO:-0330
TZNAME:UYT
DTSTART:19200501T000000
RDATE:19200501T000000
X-RADICALE-NAME:America/Montevideo
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0330
TZOFFSETTO:-0300
TZNAME:UYHST
DTSTART:19231002T000000
RDATE:19231002T000000
RDATE:19241001T000000
RDATE:19251001T000000
RDATE:19331029T000000
RDATE:19341028T000000
RDATE:19351027T000000
RDATE:19361101T000000
RDATE:19371031T000000
RDATE:19381030T000000
RDATE:19391029T000000
RDATE:19401027T000000
RDATE:19410801T000000
X-RADICALE-NAME:America/Montevideo
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0300
TZOFFSETTO:-0330
TZNAME:UYT
DTSTART:19240401T000000
RDATE:19240401T000000
RDATE:19250401T000000
RDATE:19260401T000000
RDATE:19340401T000000
RDATE:19350331T000000
RDATE:19360329T000000
RDATE:19370328T000000
RDATE:19380327T000000
RDATE:19390326T000000
RDATE:19400331T000000
RDATE:19410330T000000
RDATE:19420101T000000
X-RADICALE-NAME:America/Montevideo
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0330
TZOFFSETTO:-0200
TZNAME:UYST
DTSTART:19421214T000000
RDATE:19421214T000000
X-RADICALE-NAME:America/Montevideo
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0200
TZOFFSETTO:-0300
TZNAME:UYT
DTSTART:19430314T000000
RDATE:19430314T000000
RDATE:19591115T000000
RDATE:19600306T000000
RDATE:19650926T000000
RDATE:19661031T000000
RDATE:19671031T000000
RDATE:19720815T000000
RDATE:19761001T000000
RDATE:19780401T000000
RDATE:19800501T000000
RDATE:19880314T000000
RDATE:19890312T000000
RDATE:19900304T000000
RDATE:19910303T000000
RDATE:19920301T000000
RDATE:19930228T000000
RDATE:20050327T020000
RDATE:20060312T020000
X-RADICALE-NAME:America/Montevideo
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0200
TZNAME:UYST
DTSTART:19590524T000000
RDATE:19590524T000000
RDATE:19600117T000000
RDATE:19650404T000000
RDATE:19660403T000000
RDATE:19670402T000000
RDATE:19720424T000000
RDATE:19771204T000000
RDATE:19791001T000000
RDATE:19871214T000000
RDATE:19881211T000000
RDATE:19891029T000000
RDATE:19901021T000000
RDATE:19911027T000000
RDATE:19921018T000000
RDATE:20040919T000000
RDATE:20051009T020000
X-RADICALE-NAME:America/Montevideo
END:DAYLIGHT
BEGIN:DAYLIGHT
TZOFFSETFROM:-0300
TZOFFSETTO:-0230
TZNAME:UYHST
DTSTART:19680527T000000
RDATE:19680527T000000
RDATE:19690527T000000
RDATE:19700527T000000
RDATE:19740310T000000
X-RADICALE-NAME:America/Montevideo
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0230
TZOFFSETTO:-0300
TZNAME:UYT
DTSTART:19681202T000000
RDATE:19681202T000000
RDATE:19691202T000000
RDATE:19701202T000000
X-RADICALE-NAME:America/Montevideo
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0230
TZOFFSETTO:-0200
TZNAME:UYST
DTSTART:19741222T000000
RDATE:19741222T000000
X-RADICALE-NAME:America/Montevideo
END:DAYLIGHT
X-RADICALE-NAME:America/Montevideo
END:VTIMEZONE