How can I use SSIS submit XML to a php file ?

Use Script Task and do post as :

public static string POST(string postData, string url, string referer, string cookie)
{
    string retValue = string.Empty;
    try
    {
        byte[] byteArray = Encoding.UTF8.GetBytes(postData);
        HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
        request.Method = "POST";
        request.KeepAlive = true;
        request.AllowAutoRedirect = false;
        request.Accept = "*/*";
        request.ContentType = "text/xml";
        if (!string.IsNullOrEmpty(cookie))
            request.Headers.Add(HttpRequestHeader.Cookie, cookie);

        if (!string.IsNullOrEmpty(referer))
            request.Referer = referer;
        request.ContentLength = byteArray.Length;
        request.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.0.5) Gecko/2008120122 Firefox/3.0.5";
        //   request.Proxy = null;
        Stream dataStream = request.GetRequestStream();
        dataStream.Write(byteArray, 0, byteArray.Length);
        dataStream.Close();
        try
        {
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            Stream dataResponseStream = response.GetResponseStream();
            StreamReader SR = new StreamReader(dataResponseStream, Encoding.UTF8);
            retValue = SR.ReadToEnd();
            response.Close();
            dataStream.Close();
            SR.Close();
            request.Abort();
        }
        catch
        {
        }
    }
    catch
    {
    }
    return retValue;
}

how to call the above method :
string postdata = oReqDoc.InnerXml; //oReqDoc is the XMLDoc you need to post. If you have xml as in text form simply sent it.
string url ="http://www.abc.com/status.php php";
pass referrer and cookie as ""
now call POST as :

string strReponse = POST(postdata, url, "", "");

now you can inspect if you have got the right output xml.

you can try the following snippet too to convert string to xml:

XmlDocument doc = new XmlDocument{ XmlResolver = null };
            doc.LoadXml(strReponse);
            XmlNode newNode = doc.DocumentElement; 

Note: You may need following namespaces:

using System.Net;
using System.IO;
using System.Web;
using System.Xml;

Thanks,

Kuthuparakkal