diff --git a/src/conf.py b/src/conf.py
index 07294f9e9..8c87dd636 100644
--- a/src/conf.py
+++ b/src/conf.py
@@ -114,14 +114,13 @@ supybot.register('channels', SpaceSeparatedListOfChannels(['#supybot'], """
 Determines what channels the bot will join when it connects to the server."""))
 
 class ValidPrefixChars(registry.String):
-    def set(self, s):
-        registry.String.set(self, s)
-        if self.value.translate(string.ascii,
-                                '`~!@#$%^&*()_-+=[{}]\\|\'";:,<.>/?'):
+    def setValue(self, v):
+        if v.translate(string.ascii, '`~!@#$%^&*()_-+=[{}]\\|\'";:,<.>/?'):
             raise registry.InvalidRegistryValue, \
                   'Value must contain only ~!@#$%^&*()_-+=[{}]\\|\'";:,<.>/?'
+        registry.String.setValue(self, v)
 
-supybot.register('prefixChars', ValidPrefixChars('@', """Determines what prefix
+supybot.register('prefixChars', ValidPrefixChars('', """Determines what prefix
 characters the bot will reply to.  A prefix character is a single character
 that the bot will use to determine what messages are addressed to it; when
 there are no prefix characters set, it just uses its nick."""))
@@ -361,20 +360,12 @@ supybot.drivers.register('poll', registry.Float(1.0, """Determines the default
 length of time a driver should block waiting for input."""))
 
 class ValidDriverModule(registry.String):
-    def set(self, s):
-        original = getattr(self, 'value', self.default)
-        registry.String.set(self, s)
-        if self.value not in ('socketDrivers',
-                              'twistedDrivers',
-                              'asyncoreDrivers'):
-            self.value = original
+    def setValue(self, v):
+        if v not in ('socketDrivers', 'twistedDrivers', 'asyncoreDrivers'):
             raise registry.InvalidRegistryValue, \
                   'Value must be one of "socketDrivers", "asyncoreDrivers", ' \
                   'or twistedDrivers.'
-        else:
-            # TODO: check to make sure Twisted is available if it's set to
-            # twistedDrivers.
-            pass
+        registry.String.setValue(self, v)
 
 supybot.drivers.register('module', ValidDriverModule('socketDrivers', """
 Determines what driver module the bot will use.  socketDrivers, a simple
diff --git a/src/log.py b/src/log.py
index fa7cbd1fe..66b005d41 100644
--- a/src/log.py
+++ b/src/log.py
@@ -36,7 +36,6 @@ import fix
 import os
 import sys
 import time
-import cgitb
 import types
 import atexit
 import logging
@@ -57,16 +56,7 @@ class Formatter(logging.Formatter):
         for exn in deadlyExceptions:
             if issubclass(e.__class__, exn):
                 raise
-        if conf.supybot.log.detailedTracebacks():
-            try:
-                # Cgitb has bugs, and they break the bot.
-                #return cgitb.text((E, e, tb)).rstrip('\r\n')
-                return logging.Formatter.formatException(self, (E, e, tb))
-            except:
-                error('Cgitb.text raised an exception.')
-                return logging.Formatter.formatException(self, (E, e, tb))
-        else:
-            return logging.Formatter.formatException(self, (E, e, tb))
+        return logging.Formatter.formatException(self, (E, e, tb))
 
 
 class BetterStreamHandler(logging.StreamHandler):
@@ -198,15 +188,6 @@ conf.supybot.log.register('level', LogLevel(logging.INFO,
 """Determines what the minimum priority level logged will be.  Valid values are
 DEBUG, INFO, WARNING, ERROR, and CRITICAL, in order of increasing
 priority."""))
-conf.supybot.log.register('timestampFormat',
-registry.String('[%d-%b-%Y %H:%M:%S]',
-"""Determines the format string for timestamps in logfiles.  Refer to the
-Python documentation for the time module to see what formats are accepted."""))
-conf.supybot.log.register('detailedTracebacks', registry.Boolean(True, """
-Determines whether highly detailed tracebacks will be logged.  While more
-informative (and thus more useful for debugging) they also take a significantly
-greater amount of space in the logs.  Hopefully, however, such uncaught
-exceptions aren't very common."""))
 conf.supybot.log.register('stdout',
     registry.Boolean(True, """Determines whether the bot will log to
     stdout."""))
@@ -220,7 +201,11 @@ class BooleanRequiredFalseOnWindows(registry.Boolean):
 conf.supybot.log.stdout.register('colorized',
 BooleanRequiredFalseOnWindows(False, """Determines whether the bot's logs to
 stdout (if enabled) will be colorized with ANSI color."""))
-                          
+
+conf.supybot.log.register('timestampFormat',
+registry.String('[%d-%b-%Y %H:%M:%S]',
+"""Determines the format string for timestamps in logfiles.  Refer to the
+Python documentation for the time module to see what formats are accepted."""))
 if not os.path.exists(conf.supybot.directories.log()):
     os.mkdir(conf.supybot.directories.log(), 0755)
 
diff --git a/src/registry.py b/src/registry.py
index a6529ce63..b772b1b7f 100644
--- a/src/registry.py
+++ b/src/registry.py
@@ -283,7 +283,7 @@ class String(Value):
             v = utils.safeEval(s)
             if not isinstance(v, basestring):
                 raise ValueError
-            self.value = v
+            self.setValue(v)
         except ValueError: # This catches utils.safeEval(s) errors too.
             raise InvalidRegistryValue, '%r is not a string.' % s
 
@@ -319,8 +319,9 @@ class Regexp(Value):
         try:
             if s:
                 self.value = utils.perlReToPythonRe(s)
+                self._lastModified = time.time()
             else:
-                self.value = None
+                self.setValue(None)
             self.sr = s
         except ValueError, e:
             raise InvalidRegistryValue, '%r is not a valid regexp: %s' % (s, e)
@@ -328,7 +329,7 @@ class Regexp(Value):
     def setValue(self, v):
         if v is None:
             self.sr = ''
-            self.value = None
+            Value.setValue(self, None)
         else:
             raise InvalidRegistryValue, \
                   'Can\'t set to a regexp, there would be an inconsistency ' \