diff --git a/CHANGELOG b/CHANGELOG
index a0cc2c0..2325de0 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,11 @@
+
+Version 0.5.0   - 15 September 2002
+  * Fixed a bug where mailbox locking would fail under Solaris. (Thanks Mark
+    Sheller)
+  * Fixed a bug where archiving maildir mailboxes without a 'Received Date' or
+    'From' header would fail. (Thanks Hugo van der Merwe)
+  * Removed yet another bug where messages dated on the Unix epoch would fail.
+
 Version 0.4.9   - 18 August 2002
   * Fixed a bug where an exception was thrown if a message was dated exactly
     on the Unix epoch.
diff --git a/FAQ b/FAQ
index 8708be0..a2e5648 100644
--- a/FAQ
+++ b/FAQ
@@ -5,3 +5,12 @@
 I am quite happy to add bzip2 support to archivemail as soon as a 'bzip2'
 module (similar to the gzip module) is available for python.  
 [ Hint hint ;) ]
+
+
+2. Can you add a switch to archive mailboxes greater than a certain size?
+-------------------------------------------------------------------------
+
+If you are using mbox format mailboxes instead, use the find(1) command instead, it is more flexible:
+
+    find $HOME/Mail -type f ! -name '*archive*' 
+
diff --git a/Makefile b/Makefile
index a57b86d..5665421 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 
-VERSION=0.4.9
+VERSION=0.5.0
 VERSION_TAG=v$(subst .,_,$(VERSION))
 TARFILE=archivemail-$(VERSION).tar.gz
 
diff --git a/TODO b/TODO
index 2f3dc0a..6c0e386 100644
--- a/TODO
+++ b/TODO
@@ -1,5 +1,5 @@
 
-Goals for next minor release (0.5.0):
+Goals for next minor release (0.5.1):
 -------------------------------------
 * When you get a file-not-found in the 6th mailbox of 10, it aborts the whole
   run. Better to fail gracefully and keep going.
@@ -21,7 +21,3 @@ Longer Term goals:
   - is this a good idea?
 * Add option to archive depending on number of messages
   - is this a good idea?
-* Test for missing compression programs 
-  - is this a waste of time?
-* IMAP support
-  - is this outside our scope?
diff --git a/archivemail.py b/archivemail.py
index a9c882a..ea7c5e5 100755
--- a/archivemail.py
+++ b/archivemail.py
@@ -22,7 +22,7 @@ Website: http://archivemail.sourceforge.net/
 """
 
 # global administrivia 
-__version__ = "archivemail v0.4.9"
+__version__ = "archivemail v0.5.0"
 __cvs_id__ = "$Id$"
 __copyright__ = """Copyright (C) 2002  Paul Rodger <paul@paulrodger.com>
 This is free software; see the source for copying conditions. There is NO
@@ -51,6 +51,7 @@ import getopt
 import gzip
 import mailbox
 import os
+import pwd
 import re
 import rfc822
 import shutil
@@ -274,13 +275,13 @@ class Mbox(mailbox.UnixMailbox):
     original_mode = None # file permissions to preserve
     starting_size = None # file size of mailbox on open
 
-    def __init__(self, path, mode="r"):
+    def __init__(self, path, mode="r+"):
         """Constructor for opening an existing 'mbox' mailbox.
         Extends constructor for mailbox.UnixMailbox()
 
         Named Arguments:
         path -- file name of the 'mbox' file to be opened
-        mode -- mode to open the file in (default is read-only)
+        mode -- mode to open the file in (default is read-write)
 
         """
         assert(path)
@@ -653,22 +654,32 @@ def make_mbox_from(message):
 
     """
     assert(message)
-    address_header = message.get('Return-path')
-    if not address_header:
-        vprint("make_mbox_from: no Return-path -- using 'From:' instead!")
-        address_header = message.get('From')
-    (name, address) = rfc822.parseaddr(address_header)
-
+    address = guess_return_path(message)
     time_message = guess_delivery_time(message)
-    assert(time_message)
     gm_date = time.gmtime(time_message)
     assert(gm_date)
     date_string = time.asctime(gm_date)
-
     mbox_from = "From %s %s\n" % (address, date_string)
     return mbox_from
 
 
+def guess_return_path(message):
+    """Return a guess at the Return Path address of an rfc822 message"""
+    assert(message)
+
+    for header in ('Return-path', 'From'):
+        address_header = message.get('header')
+        if address_header:
+            (name, address) = rfc822.parseaddr(address_header)
+            if address:
+                return address
+    # argh, we can't find any valid 'Return-path' guesses - just 
+    # just use the current unix username like mutt does
+    login = pwd.getpwuid(os.getuid())[0]
+    assert(login)
+    return login
+
+
 def guess_delivery_time(message):
     """Return a guess at the delivery date of an rfc822 message""" 
     assert(message)
@@ -691,7 +702,6 @@ def guess_delivery_time(message):
         if date:
             try:
                 time_message = time.mktime(date)
-                assert(time_message)
                 vprint("using valid time found from unix 'From_' header")
                 return time_message
             except (ValueError, OverflowError): pass
diff --git a/setup.py b/setup.py
index 913c7a3..e2730d7 100755
--- a/setup.py
+++ b/setup.py
@@ -19,7 +19,7 @@ check_python_version()  # define & run this early - 'distutils.core' is new
 from distutils.core import setup
 
 setup(name="archivemail",
-      version="0.4.9",
+      version="0.5.0",
       description="archive and compress old email",
       license="GNU GPL",
       url="http://archivemail.sourceforge.net/",