Using HttpResponse succeeds only after several tries   

Using the below code for posting xml content throws "Badrequest (400)" and 
only succeeeds after 3 or 4 tries. Hugely appreciate if somebody knows how to 
fix this.

oHttpRequest = 
(HttpWebRequest)WebRequest.Create(GlobalConfiguration.GetPartnerSetting(PARTNER_NAME, "ResidentURL"));
			oHttpRequest.Timeout = 
int.Parse(GlobalConfiguration.GetPartnerSetting(PARTNER_NAME, 
"GatewayTimeoutMS"));
			oHttpRequest.Method = "post";
			oHttpRequest.ContentType = "text/xml";
			oHttpRequest.ContentLength = arrPostData.Length;
           //The foloowing 
            oHttpRequest.AllowWriteStreamBuffering = true;
            oHttpRequest.KeepAlive = true;

			oRequestStream = oHttpRequest.GetRequestStream();
			oRequestStream.Write(arrPostData, 0, arrPostData.Length);
            oRequestStream.Flush();
			oRequestStream.Close();

			//Make the request to the remote server
			try
			{
                                                     //This is where it 
throws the BadRequest error
				oHttpResponse = (HttpWebResponse)oHttpRequest.GetResponse();
			}
			catch (Exception ex)
			{
				throw new ApplicationException("The remote server could not be 
contacted.  " + ex.Message + ".", ex);
			}

date: Wed, 5 Dec 2007 09:47:01 -0800   author:   redmond