Updated documentation to include gotchas for existing models

README

@@ -111,6 +111,25 @@ suggest NOT using SortableStackedInline. I'm currently working on
 a way to make this more usable.
 
 
+Potential Gotcha
+=============
+
+If you have an existing model that you're now making Sortable, existing
+rows won't have an "order" attribute. Django-admin-sortable depends on
+being able to leverage an aggregate Max to determine if a model is sortable.
+
+A good rule of thumb if you're adding django-admin-sortable to an existing
+project is to create a Data Migration using South to set the "order" column
+according to your needs.
+
+For example, if you have a SortableForeignKey field, you would need to set
+the "order" column relative to that field, instead of setting the "order"
+column in linear succession.
+
+See: http://south.readthedocs.org/en/latest/tutorial/part3.html for more
+information on Data Migrations.
+
+
 Rationale
 =============
 Other projects have added drag-and-drop ordering to the ChangeList
@@ -130,9 +149,10 @@ Status
 admin-sortable is currently used in production.
 
 
-What's new in 1.3.7?
+What's new in 1.3.8?
 =============
 - CSS fixes for tabular inlines courtesty of @ionelmc: https://github.com/ionelmc
+- Updated documentation
 
 Features
 =============

adminsortable/__init__.py

@@ -1,4 +1,4 @@
-VERSION = (1, 3, 7)  # following PEP 386
+VERSION = (1, 3, 8)  # following PEP 386
 DEV_N = None