Index: defaulttags.py
===================================================================
--- defaulttags.py	(revision 4810)
+++ defaulttags.py	(working copy)
@@ -491,7 +491,7 @@
 
     but obviously much cleaner!
     """
-    bits = token.contents.split()[1:]
+    bits = token.split_contents()[1:]
     if len(bits) < 1:
         raise TemplateSyntaxError, "'firstof' statement requires at least one argument"
     return FirstOfNode(bits)