This is what I'm using, I just successfully sent an email with a file attached.
Code:
<characteristic type="EMAIL2">
<characteristic type="{b3008120-d08a-40c5-bf38-0c126bd71a47}">
<parm name="SERVICENAME" value="Gmail" />
<parm name="SERVICETYPE" value="IMAP4" />
<parm name="INSERVER" value="imap.gmail.com" />
<parm name="OUTSERVER" value="smtp.gmail.com" />
<parm name="NAME" value="Craig" />
<parm name="AUTHNAME" value="deleted" />
<parm name="AUTHSECRET" value="deleted" />
<parm name="DOMAIN" value="" />
<parm name="REPLYADDR" value="deleted" />
<parm name="LINGER" value="15" />
<parm name="RETRIEVE" value="-1" />
<parm name="KEEPMAX" value="-1" />
<parm name="DWNDAY" value="3" />
<parm name="AUTHREQUIRED" value="1" />
<parm name="SMTPALTENABLED" value="0" />
<characteristic type="TAGPROPS">
<parm name="8128000B" value="1"/>
<parm name="812C000B" value="1"/>
</characteristic>
</characteristic>
</characteristic>