X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~matthewv/git?a=blobdiff_plain;f=gooswapper.py;h=75edd3febb2c54bcd77979cfadd513b4268f169e;hb=3ab26f0d9fff9530325a1c227f4f2e8da81b6f58;hp=f3c73a0610e4c4dcaab4faeb39f249957a1954ac;hpb=5ed38486a4eba80d8386bd69e2d68cbe6de33a27;p=gooswapper

diff --git a/gooswapper.py b/gooswapper.py
index f3c73a0..75edd3f 100644
--- a/gooswapper.py
+++ b/gooswapper.py
@@ -54,7 +54,10 @@ class ex_gcal_link(exchangelib.ExtendedProperty):
     property_name = "google calendar event id"
     property_type = 'String'
 
-exchangelib.CalendarItem.register('gcal_link',ex_gcal_link)
+try:
+    exchangelib.CalendarItem.get_field_by_fieldname('gcal_link')
+except ValueError:
+    exchangelib.CalendarItem.register('gcal_link',ex_gcal_link)
 
 #useful if you want to replay an event
 def drop_from_ex_cache(itemid):