--- a/Lib/json/decoder.py	Fri Jun 29 01:05:26 2012 +0200
+++ b/Lib/json/decoder.py	Fri Jun 29 01:58:26 2012 +0200
@@ -173,7 +173,8 @@
                 pairs = object_hook(pairs)
             return pairs, end + 1
         elif nextchar != '"':
-            raise ValueError(errmsg("Expecting property name", s, end))
+            raise ValueError(errmsg(
+                "Expecting property name enclosed in double quotes", s, end))
     end += 1
     while True:
         key, end = scanstring(s, end, strict)
@@ -183,7 +184,7 @@
         if s[end:end + 1] != ':':
             end = _w(s, end).end()
             if s[end:end + 1] != ':':
-                raise ValueError(errmsg("Expecting : delimiter", s, end))
+                raise ValueError(errmsg("Expecting ':' delimiter", s, end))
         end += 1
 
         try:
@@ -211,12 +212,13 @@
         if nextchar == '}':
             break
         elif nextchar != ',':
-            raise ValueError(errmsg("Expecting , delimiter", s, end - 1))
+            raise ValueError(errmsg("Expecting ',' delimiter", s, end - 1))
         end = _w(s, end).end()
         nextchar = s[end:end + 1]
         end += 1
         if nextchar != '"':
-            raise ValueError(errmsg("Expecting property name", s, end - 1))
+            raise ValueError(errmsg(
+                "Expecting property name enclosed in double quotes", s, end - 1))
     if object_pairs_hook is not None:
         result = object_pairs_hook(pairs)
         return result, end
@@ -250,7 +252,7 @@
         if nextchar == ']':
             break
         elif nextchar != ',':
-            raise ValueError(errmsg("Expecting , delimiter", s, end))
+            raise ValueError(errmsg("Expecting ',' delimiter", s, end))
         try:
             if s[end] in _ws:
                 end += 1