diff --git a/tailbone/api/master.py b/tailbone/api/master.py
index 27030f5b..7cb911be 100644
--- a/tailbone/api/master.py
+++ b/tailbone/api/master.py
@@ -177,17 +177,14 @@ class APIMasterView(APIView):
         """
         return self.sortcol(order_by)
 
-    def sortcol(self, *args):
+    def sortcol(self, field_name, model_name=None):
         """
         Return a simple ``SortColumn`` object which denotes the field and
         optionally, the model, to be used when sorting.
         """
-        if len(args) == 1:
-            return SortColumn(args[0])
-        elif len(args) == 2:
-            return SortColumn(args[1], args[0])
-        else:
-            raise ValueError("must pass 1 arg (field_name) or 2 args (model_name, field_name)")
+        if not model_name:
+            model_name = self.model_class.__name__
+        return SortColumn(field_name, model_name)
 
     def join_for_sort_spec(self, query, sort_spec):
         """
diff --git a/tailbone/api/workorders.py b/tailbone/api/workorders.py
index 315a92bb..d559589d 100644
--- a/tailbone/api/workorders.py
+++ b/tailbone/api/workorders.py
@@ -66,6 +66,12 @@ class WorkOrderView(APIMasterView):
             'date_delivered': six.text_type(workorder.date_delivered or ''),
         }
 
+    def create_object(self, data):
+
+        # invoke the handler instead of normal API CRUD logic
+        workorder = self.workorder_handler.make_workorder(self.Session(), **data)
+        return workorder
+
     def update_object(self, workorder, data):
         date_fields = [
             'date_submitted',
@@ -79,7 +85,7 @@ class WorkOrderView(APIMasterView):
             if field in data:
                 if data[field] == '':
                     data[field] = None
-                else:
+                elif not isinstance(data[field], datetime.date):
                     date = datetime.datetime.strptime(data[field], '%Y-%m-%d').date()
                     data[field] = date