diff -r 6641e941ef1e -r ff1a9aa48cfd app/django/contrib/gis/geos/error.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/contrib/gis/geos/error.py	Tue Oct 14 16:00:59 2008 +0000
@@ -0,0 +1,20 @@
+"""
+ This module houses the GEOS exceptions, specifically, GEOSException and
+ GEOSGeometryIndexError.
+"""
+
+class GEOSException(Exception):
+    "The base GEOS exception, indicates a GEOS-related error."
+    pass
+
+class GEOSIndexError(GEOSException, KeyError):
+    """
+    This exception is raised when an invalid index is encountered, and has
+    the 'silent_variable_feature' attribute set to true.  This ensures that
+    django's templates proceed to use the next lookup type gracefully when
+    an Exception is raised.  Fixes ticket #4740.
+    """
+    # "If, during the method lookup, a method raises an exception, the exception
+    #  will be propagated, unless the exception has an attribute 
+    #  `silent_variable_failure` whose value is True." -- Django template docs.
+    silent_variable_failure = True