diff --git a/src/addresses.py b/src/addresses.py
index a6a571f6..1db2105d 100644
--- a/src/addresses.py
+++ b/src/addresses.py
@@ -97,13 +97,18 @@ def calculateInventoryHash(data):
     return sha2.digest()[0:32]
 
 def encodeAddress(version,stream,ripe):
-    if version >= 2:
+    if version >= 2 and version < 4:
         if len(ripe) != 20:
             raise Exception("Programming error in encodeAddress: The length of a given ripe hash was not 20.")
         if ripe[:2] == '\x00\x00':
             ripe = ripe[2:]
         elif ripe[:1] == '\x00':
             ripe = ripe[1:]
+    elif version == 4:
+        if len(ripe) != 20:
+            raise Exception("Programming error in encodeAddress: The length of a given ripe hash was not 20.")
+        ripe = ripe.lstrip('\x00')
+
     a = encodeVarint(version) + encodeVarint(stream) + ripe
     sha = hashlib.new('sha512')
     sha.update(a)
@@ -164,7 +169,7 @@ def decodeAddress(address):
     #print 'addressVersionNumber', addressVersionNumber
     #print 'bytesUsedByVersionNumber', bytesUsedByVersionNumber
 
-    if addressVersionNumber > 3:
+    if addressVersionNumber > 4:
         print 'cannot decode address version numbers this high'
         status = 'versiontoohigh'
         return status,0,0,0
@@ -191,6 +196,15 @@ def decodeAddress(address):
             return 'ripetoolong',0,0,0
         else:
             return 'otherproblem',0,0,0
+    elif addressVersionNumber == 4:
+        if len(data[bytesUsedByVersionNumber+bytesUsedByStreamNumber:-4]) > 20:
+            return 'ripetoolong',0,0,0
+        elif len(data[bytesUsedByVersionNumber+bytesUsedByStreamNumber:-4]) < 4:
+            return 'ripetooshort',0,0,0
+        else:
+            x00string = '\x00' * (20 - len(data[bytesUsedByVersionNumber+bytesUsedByStreamNumber:-4]))
+            return status,addressVersionNumber,streamNumber,x00string+data[bytesUsedByVersionNumber+bytesUsedByStreamNumber:-4]
+        
 
 def addBMIfNotPresent(address):
     address = str(address).strip()
diff --git a/src/class_receiveDataThread.py b/src/class_receiveDataThread.py
index 19df1bdc..b5aa5893 100644
--- a/src/class_receiveDataThread.py
+++ b/src/class_receiveDataThread.py
@@ -1220,7 +1220,7 @@ class receiveDataThread(threading.Thread):
         if addressVersion == 0:
             print '(Within processpubkey) addressVersion of 0 doesn\'t make sense.'
             return
-        if addressVersion >= 4 or addressVersion == 1:
+        if addressVersion > 3 or addressVersion == 1:
             with shared.printLock:
                 print 'This version of Bitmessage cannot handle version', addressVersion, 'addresses.'
 
diff --git a/src/class_singleWorker.py b/src/class_singleWorker.py
index b29b7f8d..a3d0a0c5 100644
--- a/src/class_singleWorker.py
+++ b/src/class_singleWorker.py
@@ -535,6 +535,8 @@ class singleWorker(threading.Thread):
             pubEncryptionKeyBase256 = pubkeyPayload[
                 readPosition:readPosition + 64]
             readPosition += 64
+            
+            # Let us fetch the amount of work required by the recipient.
             if toAddressVersionNumber == 2:
                 requiredAverageProofOfWorkNonceTrialsPerByte = shared.networkDefaultProofOfWorkNonceTrialsPerByte
                 requiredPayloadLengthExtraBytes = shared.networkDefaultPayloadLengthExtraBytes
@@ -569,6 +571,7 @@ class singleWorker(threading.Thread):
                             requiredPayloadLengthExtraBytes) / shared.networkDefaultPayloadLengthExtraBytes)).arg(unicode(strftime(shared.config.get('bitmessagesettings', 'timeformat'), localtime(int(time.time()))), 'utf-8')))))
                         continue
 
+
             embeddedTime = pack('>Q', (int(time.time()) + random.randrange(
                 -300, 300)))  # the current time plus or minus five minutes. We will use this time both for our message and for the ackdata packed within our message.
             if fromAddressVersionNumber == 2:
diff --git a/src/shared.py b/src/shared.py
index fb19da26..f20c49e2 100644
--- a/src/shared.py
+++ b/src/shared.py
@@ -20,6 +20,7 @@ import sys
 import stat
 import threading
 import time
+from os import path, environ
 
 # Project imports.
 from addresses import *
@@ -125,7 +126,6 @@ def assembleVersionMessage(remoteHost, remotePort, myStreamNumber):
 
 def lookupAppdataFolder():
     APPNAME = "PyBitmessage"
-    from os import path, environ
     if sys.platform == 'darwin':
         if "HOME" in environ:
             dataFolder = path.join(os.environ["HOME"], "Library/Application Support/", APPNAME) + '/'
@@ -239,7 +239,7 @@ def reloadMyAddressHashes():
             if isEnabled:
                 hasEnabledKeys = True
                 status,addressVersionNumber,streamNumber,hash = decodeAddress(addressInKeysFile)
-                if addressVersionNumber == 2 or addressVersionNumber == 3:
+                if addressVersionNumber == 2 or addressVersionNumber == 3 or addressVersionNumber == 4:
                     # Returns a simple 32 bytes of information encoded in 64 Hex characters,
                     # or null if there was an error.
                     privEncryptionKey = decodeWalletImportFormat(
@@ -250,7 +250,7 @@ def reloadMyAddressHashes():
                         myAddressesByHash[hash] = addressInKeysFile
 
                 else:
-                    logger.error('Error in reloadMyAddressHashes: Can\'t handle address versions other than 2 or 3.\n')
+                    logger.error('Error in reloadMyAddressHashes: Can\'t handle address versions other than 2, 3, or 4.\n')
 
     if not keyfileSecure:
         fixSensitiveFilePermissions(appdata + 'keys.dat', hasEnabledKeys)