diff --git a/sendgrid/header.py b/sendgrid/header.py
index b981fd71d..fe8f4e5a5 100644
--- a/sendgrid/header.py
+++ b/sendgrid/header.py
@@ -71,7 +71,7 @@ def set_section(self, val):
     def add_filter_setting(self, fltr, setting, val):
         if 'filters' not in self.data:
             self.data['filters'] = {}
-        if fltr not in self.data:
+        if fltr not in self.data['filters']:
             self.data['filters'][fltr] = {}
         if 'settings' not in self.data['filters'][fltr]:
             self.data['filters'][fltr]['settings'] = {}
diff --git a/sendgrid/sendgrid.py b/sendgrid/sendgrid.py
index 82149efaa..65e572557 100644
--- a/sendgrid/sendgrid.py
+++ b/sendgrid/sendgrid.py
@@ -14,18 +14,20 @@ class Sendgrid(object):
     """
     Sendgrid API
     """
-    def __init__(self, username, password, secure=True):
+    def __init__(self, username, password, **opts):
         """
         Construct Sendgrid API object
 
         Args:
             username: Sendgrid uaername
             password: Sendgrid password
-            ssl: Use SSL
+            secure: Use SSL/TLS
+            user: Send mail on behalf of this user (web only)
         """
         self.username = username
         self.password = password
-        self.secure = secure
+        self.secure = opts.get('secure', True)
+        self.user = opts.get('user', None)
 
 
     @property
@@ -35,7 +37,7 @@ def web(self):
         Return web transport
         """
         from transport import web
-        return web.Http(self.username, self.password, self.secure)
+        return web.Http(self.username, self.password, ssl=self.secure, user=self.user)
 
 
     @property
@@ -45,4 +47,4 @@ def smtp(self):
         Return smtp transport
         """
         from transport import smtp
-        return smtp.Smtp(self.username, self.password, self.secure)
\ No newline at end of file
+        return smtp.Smtp(self.username, self.password, tls=self.secure)
diff --git a/sendgrid/transport/smtp.py b/sendgrid/transport/smtp.py
index ac8aea7ab..ddb4edba3 100644
--- a/sendgrid/transport/smtp.py
+++ b/sendgrid/transport/smtp.py
@@ -23,7 +23,7 @@ class Smtp(object):
     """
     HOSTPORT = ('smtp.sendgrid.net', 587)
 
-    def __init__(self, username, password, tls=True):
+    def __init__(self, username, password, **opts):
         """
         Construct smtp transport object
 
@@ -34,7 +34,7 @@ def __init__(self, username, password, tls=True):
         """
         self.username = username
         self.password = password
-        self.tls = tls
+        self.tls = opts.get('tls', True)
 
     def send(self, message):
         """
diff --git a/sendgrid/transport/web.py b/sendgrid/transport/web.py
index 023eb0fb3..1d543a30d 100644
--- a/sendgrid/transport/web.py
+++ b/sendgrid/transport/web.py
@@ -13,18 +13,22 @@ class Http(object):
     """
     Transport to send emails using http
     """
-    def __init__(self, username, password, ssl=True):
+    HOSTPORT = ('sendgrid.com',)
+
+    def __init__(self, username, password, **opts):
         """
         Construct web transport object
 
         Args:
-            username: Sendgrid uaername
+            username: Sendgrid username
             password: Sendgrid password
             ssl: Use SSL
+            user: Send mail on behalf of this user
         """
         self.username = username
         self.password = password
-        self.ssl = ssl
+        self.ssl = opts.get('ssl', True)
+        self.user = opts.get('user', None)
 
     def send(self, message):
         """
@@ -39,9 +43,12 @@ def send(self, message):
         Raises:
             SGServiceException: on error
         """
-        url = "https://sendgrid.com/api/mail.send.json"
+        protocol = "https://"
         if not self.ssl:
-            url = "http://sendgrid.com/api/mail.send.json"
+            protocol = "http://"
+        endpoint = "/api/mail.send.json"
+
+        url = protocol + ":".join(map(str, self.HOSTPORT)) + endpoint
 
         data = {
             'api_user': self.username,
@@ -73,6 +80,7 @@ def send(self, message):
             'bcc': message.bcc,
             'fromname': message.from_name,
             'replyto': message.reply_to,
+            'user': self.user,
             }
 
         for key in optional_params:
@@ -85,7 +93,10 @@ def send(self, message):
             f = urllib2.urlopen(req)
             output = f.read()
         except IOError, e:
-            output = e.read()
+            try:
+                output = e.read()
+            except AttributeError:
+                raise exceptions.SGServiceException(e)
 
         output = json.loads(output)