How to get origid (or the original sender)?

Hi,
I m playing with the soap method, and I have some problems to retreive the original id of a forwarded mail.
This is the header of a message retreived by SearchRequest query.

I thank you in advance for your help.

PHP Code:

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<m id="6675" rev="19711" d="1325926013000" cm="1" s="7776" score="1.0" sd="1325926013000" sf="1325926013000" l="2" cid="6668">
    <e d="Stan" t="f" p="Stan" a="xxx@ccc.com" />
    <e d="stan" t="t" a="xxx@ccc.com" />
    <su>Fwd: Roles</su>
    <fr>-- Mail transféré -- De: zzzz@aaa.com À: "Stan" &lt;xxx@ccc.com&gt; Envoyé: Vendredi 6 Janvier 2012 22:37:04 Objet: ...</fr>
    <mid>&lt;110425122.84718.1325926013304.JavaMail.root@SV-TCA-ZIMDIA01.cigg.ad&gt;</mid>
    <mp s="6833" part="TEXT" ct="multipart/alternative">
        <mp body="1" s="2607" part="1" ct="text/plain">
            <content>
                  bla bla bla
            </content>
        </mp>
        <mp s="3904" part="2" ct="text/html" />
    </mp>
</m> 


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