diff --git a/grandlyon/scripts/generate-geojson.py b/grandlyon/scripts/generate-geojson.py
index f0e752f..7c79827 100644
--- a/grandlyon/scripts/generate-geojson.py
+++ b/grandlyon/scripts/generate-geojson.py
@@ -29,7 +29,7 @@ for formdef in FormDef.select():
         formdata = formdef.data_class().get(formdata_id)
         formdata_vars = formdata.get_substitution_variables()
         for field in ('numero', 'voie', 'commune', 'message', 'type_probleme'):
-            feature['properties'][field] = formdata_vars.get('form_var_%s' % field)
+            feature['properties'][field] = unicode(formdata_vars.get('form_var_%s' % field))
         feature['properties']['datetime'] = formdata_vars['form_receipt_datetime'].strftime('%d/%m/%Y %H:%M')
         feature['properties']['reference'] = '%s:%s' % (formdata_vars['form_slug'], formdata_id)