Look at this. It may give you an idea how to "pull" payment info about a transaction whose code the user has entered in a form. This is assuming that you have set up everything with Safcom as needed, including giving them an IP to be sending your IPN information to :

    public static function pull($terminal_msisdn, $password, $code)
    {
        $post_string = "<soapenv:Envelope xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:ipn=\"http://ipn/\">
            <soapenv:Header/>
            <soapenv:Body>
            <ipn:retrieveTransaction>
            <transactionCode>{$code}</transactionCode>
            <senderMsisdn></senderMsisdn>
            <terminalMsisdn>{$terminal_msisdn}</terminalMsisdn>
            <password>{$password}</password>
            </ipn:retrieveTransaction>
            </soapenv:Body>
            </soapenv:Envelope>";

        $url = "https://www.safaricom.co.ke/IPN/IpnWebRetrieval";
        $response = curl::post($url, $post_string);

        $xml = preg_replace("/(<\/?)(\w+):([^>]*>)/", "$1$2$3", $response);
        $xml = simplexml_load_string($xml);

        if (isset($xml->soapBody->ns2retrieveTransactionResponse->transaction)) {
            return $xml->soapBody->ns2retrieveTransactionResponse->transaction;
        }

        return false;


    }