diff --git a/src/registry.py b/src/registry.py
index 8441f4821..54baf5239 100644
--- a/src/registry.py
+++ b/src/registry.py
@@ -128,8 +128,7 @@ class Group(object):
         v = self.__class__(self.default, self.help)
         v.set(s)
         v.__class__ = self.X
-        # Undo this later unless you understand why you commented it out!
-        #v.supplyDefault = False
+        v.supplyDefault = False
         v.help = '' # Clear this so it doesn't print a bazillion times.
         self.register(attr, v)
         return v
@@ -198,6 +197,7 @@ class Group(object):
 
 
 class Value(Group):
+    # Docstrings should start with, "Value must be ..." whenever possible.
     """Invalid registry value.  If you're getting this message, report it,
     because someone forgot to put a proper help string here."""
     def __init__(self, default, help,
@@ -299,7 +299,7 @@ class Float(Value):
             self.error()
 
 class String(Value):
-    """Value is not a valid Python string."""
+    """Value must be a valid Python string."""
     def set(self, s):
         if not s:
             s = '""'
@@ -313,18 +313,22 @@ class String(Value):
         except ValueError: # This catches utils.safeEval(s) errors too.
             self.error()
 
+class MetaOnlySomeStrings(type):
+    def __new__(cls, name, bases, dict):
+        if 'validStrings' in dict:
+            validStrings = dict['validStrings']
+            dict['__doc__'] = 'Value must be one of %s.' % \
+                              utils.commaAndify(validStrings, And='or')
+        return type.__new__(cls, name, bases, dict)
+    
 class OnlySomeStrings(String):
     validStrings = ()
+    __metaclass__ = MetaOnlySomeStrings
     def __init__(self, *args, **kwargs):
         assert self.validStrings, 'There must be some valid strings.  ' \
                                   'This is a bug.'
         String.__init__(self, *args, **kwargs)
         
-    def error(self):
-        raise InvalidRegistryValue, \
-              'That is not a valid value.  Valid values include %s.' % \
-              utils.commaAndify(map(repr, self.validStrings))
-
     def normalize(self, s):
         lowered = s.lower()
         L = list(map(str.lower, self.validStrings))
@@ -369,6 +373,7 @@ class StringWithSpaceOnRight(String):
         String.setValue(self, v)
 
 class Regexp(Value):
+    """Value must be a valid Python regular expression of the form m/.../"""
     def error(self, e):
         raise InvalidRegistryValue, 'Invalid regexp: %s' % e
 
@@ -396,9 +401,17 @@ class Regexp(Value):
         self() # Gotta update if we've been reloaded.
         return self.sr
         
+class MetaSeparatedListOf(type):
+    def __new__(cls, name, bases, dict):
+        if 'Value' in dict:
+            Value = dict['Value']
+            dict['__doc__'] = """Value must be a list of """
+            # XXX
+            
 class SeparatedListOf(Value):
     List = list
     Value = Value
+    Separator = None
     def splitter(self, s):
         """Override this with a function that takes a string and returns a list
         of strings."""
@@ -431,8 +444,7 @@ class SeparatedListOf(Value):
         
 class SpaceSeparatedListOfStrings(SeparatedListOf):
     Value = String
-    def splitter(self, s):
-        return s.split()
+    splitter = staticmethod(str.split)
     joiner = ' '.join
     
 class CommaSeparatedListOfStrings(SeparatedListOf):