IE dying on request.GetResponse()

[StephanieJ49]

I'm having an issue where the following code is working perfect in Chrome and FF but is dying on the bold/italic line in IE.  No error is thrown that I can tell, I have a try catch block that is printing to a text file any errors that are thrown.   The address variable is "https://api.constantcontact.com/ws/customers/[username]/contacts.  The contentType is "application/atom+xml".  The requestMethod is "POST".  The data is XML as shown below the code.  One thing I feel I should mention is that the username is an email address.  I'm assuming that this should be URL encoded. 

Any help would be appreciated.

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(address);
            request.Credentials = CreateCredentialCache(address, authenticationData);
            request.Method = requestMethod;
            request.ContentType = contentType;
            request.PreAuthenticate = true;
            request.ContentLength = data.Length;
            Stream stream = request.GetRequestStream();
            stream.Write(data, 0, data.Length);
            Stream responseStream = Stream.Null;
            try
            {
 HttpWebResponse response = (HttpWebResponse)request.GetResponse();
                Console.WriteLine(String.Format(CultureInfo.InvariantCulture,
                                                "Method {0}, response description: {1}", request.Method,
                                                response.StatusDescription));

                if (response.StatusCode == HttpStatusCode.NoContent)
                {
                    return Stream.Null;
                }
                responseStream = response.GetResponseStream();
                MemoryStream memoryStream = ReadResponseStream(responseStream);
                return memoryStream;
            }
            catch (Exception ex)
            {
                Logging.LogError("GetResponseStream: " + ex.Message);
            }
            finally
            {
                stream.Close();
                responseStream.Close();
            }
            return Stream.Null;

<entry xmlns="http://www.w3.org/2005/Atom">
	<title type="text"></title>
	<updated>2008-07-23T14:21:06.407Z</updated>
	<author></author>
	<id>data:,none</id>
	<summary type="text">Contact</summary>
	<content type="application/vnd.ctct+xml">
		<Contact xmlns="http://ws.constantcontact.com/ns/1.0/">
			<EmailAddress>email@email.com</EmailAddress>
			<FirstName>s</FirstName>
			<MiddleName></MiddleName>
			<LastName>j</LastName>
			<HomePhone>7</HomePhone>
			<Addr1></Addr1>
			<Addr2></Addr2>
			<Addr3></Addr3>
			<City></City>
			<StateCode></StateCode>
			<StateName></StateName>
			<PostalCode></PostalCode>
			<SubPostalCode></SubPostalCode>
			<CountryCode></CountryCode>
			<CompanyName>m</CompanyName>
			<JobTitle>i</JobTitle>
			<WorkPhone></WorkPhone>
			<EmailType>HTML</EmailType>
			<OptInSource>ACTION_BY_CONTACT</OptInSource>
			<Note></Note>
			<CustomField1></CustomField1>
			<CustomField2></CustomField2>
			<CustomField3></CustomField3>
			<CustomField4></CustomField4>
			<CustomField5></CustomField5>
			<CustomField6></CustomField6>
			<CustomField7></CustomField7>
			<CustomField8></CustomField8>
			<CustomField9></CustomField9>
			<CustomField10></CustomField10>
			<CustomField11></CustomField11>
			<CustomField12></CustomField12>
			<CustomField13></CustomField13>
			<CustomField14></CustomField14>
			<CustomField15></CustomField15>
			<ContactLists>
				<ContactList id="https://api.constantcontact.com/ws/customers/[username]/lists/37"/>
				<ContactList id="https://api.constantcontact.com/ws/customers/[username]/lists/39"/>
			</ContactLists>
		</Contact>
	</content>
</entry>