diff --git a/IPython/Extensions/envpersist.py b/IPython/Extensions/envpersist.py
index 9153363..a0523ba 100644
--- a/IPython/Extensions/envpersist.py
+++ b/IPython/Extensions/envpersist.py
@@ -7,13 +7,11 @@ ip = IPython.ipapi.get()
 
 import os,sys
 
-def restore_env(self):
+def restore_env(self):    
     ip = self.getapi()
     env = ip.db.get('stored_env', {'set' : {}, 'add' : [], 'pre' : []})
     for k,v in env['set'].items():
-        #print "restore alias",k,v # dbg
         os.environ[k] = v
-        self.alias_table[k] = v
     for k,v in env['add']:
         os.environ[k] = os.environ.get(k,"") + v
     for k,v in env['pre']:
diff --git a/IPython/Extensions/ipy_profile_sh.py b/IPython/Extensions/ipy_profile_sh.py
index 4064038..6c5f29c 100644
--- a/IPython/Extensions/ipy_profile_sh.py
+++ b/IPython/Extensions/ipy_profile_sh.py
@@ -90,9 +90,11 @@ def main():
         def mapper(s): return s.lower()
         
     for cmd in syscmds:
-        #print "al",cmd
+        # print "sys",cmd #dbg
         noext, ext = os.path.splitext(cmd)
-        ip.IP.alias_table[mapper(noext)] = (0,cmd)
+        key = mapper(noext)
+        if key not in ip.IP.alias_table:
+            ip.defalias(key, cmd)
 
     if 'ls' in syscmds:
         # use the colors of cygwin ls (recommended)
diff --git a/IPython/ipapi.py b/IPython/ipapi.py
index 36256b8..215eda4 100644
--- a/IPython/ipapi.py
+++ b/IPython/ipapi.py
@@ -184,6 +184,9 @@ class IPApi:
         self.IP = ip
 
         self.extensions = {}
+
+        self.dbg = DebugTools(self)
+        
         global _recent
         _recent = self
 
@@ -222,6 +225,11 @@ class IPApi:
                 
         import new
         im = new.instancemethod(func,self.IP, self.IP.__class__)
+        old = getattr(self.IP, "magic_" + magicname, None)
+        if old:
+            self.dbg.debug_stack("Magic redefinition '%s', old %s" % (magicname,
+                                 old))
+            
         setattr(self.IP, "magic_" + magicname, im)
     
     def ex(self,cmd):
@@ -355,7 +363,15 @@ class IPApi:
         
         Creates a new alias named 'bb' in ipython user namespace
         """
+
+        self.dbg.check_hotname(name)
         
+
+        if name in self.IP.alias_table:
+            self.dbg.debug_stack("Alias redefinition: '%s' => '%s' (old '%s')" %
+                             (name, cmd, self.IP.alias_table[name]))
+            
+
         if callable(cmd):
             self.IP.alias_table[name] = cmd
             import IPython.shadowns
@@ -368,7 +384,11 @@ class IPApi:
                 raise Exception('The %s and %l specifiers are mutually exclusive '
                                 'in alias definitions.')
                   
-            self.IP.alias_table[name] = (nargs,cmd)            
+            self.IP.alias_table[name] = (nargs,cmd)
+            return
+        
+        # just put it in - it's probably (0,'foo')
+        self.IP.alias_table[name] = cmd
     
     def defmacro(self, *args):
         """ Define a new macro
@@ -419,7 +439,35 @@ class IPApi:
             m.init_ipython(self)
         self.extensions[mod] = m
         return m
+    
+
+class DebugTools:
+    """ Used for debugging mishaps in api usage
+    
+    So far, tracing redefinitions is supported.
+    """
+    
+    def __init__(self, ip):
+        self.ip = ip
+        self.debugmode = False
+        self.hotnames = set()
+        
+        
+    def hotname(self, name_to_catch):
+        self.hotnames.add(name_to_catch)
+        
+    def debug_stack(self, msg = None):
+        if not self.debugmode:
+            return
         
+        import traceback
+        if msg is not None:
+            print '====== %s  ========' % msg
+        traceback.print_stack()
+
+    def check_hotname(self,name):
+        if name in self.hotnames:
+            self.debug_stack( "HotName '%s' caught" % name)
 
 def launch_new_instance(user_ns = None):
     """ Make and start a new ipython instance.
diff --git a/IPython/iplib.py b/IPython/iplib.py
index a848ae1..d8c4d3f 100644
--- a/IPython/iplib.py
+++ b/IPython/iplib.py
@@ -6,7 +6,7 @@ Requires Python 2.3 or newer.
 
 This file contains all the classes and helper functions specific to IPython.
 
-$Id: iplib.py 2637 2007-08-17 16:18:05Z vivainio $
+$Id: iplib.py 2646 2007-08-20 16:28:48Z vivainio $
 """
 
 #*****************************************************************************
@@ -579,12 +579,13 @@ class InteractiveShell(object,Magic):
         else:
             auto_alias = ()
         self.auto_alias = [s.split(None,1) for s in auto_alias]
-        # Call the actual (public) initializer
-        self.init_auto_alias()
 
         # Produce a public API instance
         self.api = IPython.ipapi.IPApi(self)
 
+        # Call the actual (public) initializer
+        self.init_auto_alias()
+
         # track which builtins we add, so we can clean up later
         self.builtins_added = {}
         # This method will add the necessary builtins for operation, but
@@ -1017,7 +1018,8 @@ class InteractiveShell(object,Magic):
         These are ALL parameter-less aliases"""
 
         for alias,cmd in self.auto_alias:
-            self.alias_table[alias] = (0,cmd)
+            self.getapi().defalias(alias,cmd)
+            
 
     def alias_table_validate(self,verbose=0):
         """Update information about the alias table.
@@ -1268,7 +1270,9 @@ want to merge them back into the new files.""" % locals()
     def init_readline(self):
         """Command history completion/saving/reloading."""
 
+
         import IPython.rlineimpl as readline
+                  
         if not readline.have_readline:
             self.has_readline = 0
             self.readline = None
@@ -1618,7 +1622,7 @@ want to merge them back into the new files.""" % locals()
         # Mark activity in the builtins
         __builtin__.__dict__['__IPYTHON__active'] += 1
 
-        if readline.have_readline:
+        if self.has_readline:
             self.readline_startup_hook(self.pre_readline)
         # exit_now is set by a call to %Exit or %Quit