diff --git a/core/config.py b/core/config.py
index 12336bc..2f788cf 100644
--- a/core/config.py
+++ b/core/config.py
@@ -21,7 +21,7 @@ if not os.path.exists('config'):
     del conf
 
 bot.config = yaml.load(open('config'))
-bot._config_dirty = False
+bot._config_dirty = True # force a rewrite on start
 bot._config_mtime = os.stat('config').st_mtime
 
 def config_dirty(self): 
diff --git a/plugins/sieve.py b/plugins/sieve.py
index 197a040..4fa147e 100644
--- a/plugins/sieve.py
+++ b/plugins/sieve.py
@@ -1,3 +1,4 @@
+import os
 import re
 
 from util import hook
@@ -16,14 +17,28 @@ def sieve_suite(bot, input, func, args):
     hook = args.get('hook', r'(.*)')
 
     if args.get('prefix', True):
-        # add a prefix, unless it's a private message
-        hook = (r'^(?:[.!]|' if input.chan != input.nick else r'^(?:[.!]?|') \
-                + input.conn.nick + r'[:,]*\s*)' + hook
+        if input.chan == input.nick: # private message, prefix not required
+            prefix = r'^(?:[.!]?|'
+        else:
+            prefix = r'^(?:[.!]|'
+        hook = prefix + input.conn.nick + r'[:,]*\s)' + hook
 
     input.re = re.match(hook, input.msg, flags=re.I)
     if input.re is None:
         return None
 
+    acl = bot.config.get('acls', {}).get(func.__name__)
+    if acl:
+        print acl
+        if 'deny-except' in acl:
+            allowed_channels = map(str.lower, acl['deny-except'])
+            if input.chan.lower() not in allowed_channels:
+                return None
+        if 'allow-except' in acl:
+            denied_channels = map(str.lower, acl['allow-except'])
+            if input.chan.lower() in denied_channels:
+                return None
+
     input.inp_unstripped = ' '.join(input.re.groups())
     input.inp = input.inp_unstripped.strip()