i don't know how to setup via cab, but with UC there is a way to setup emailaccounts: http://forum.xda-developers.com/showpost.php?p=1897000&postcount=3
EMAIL2 CSPs
All the EMAIL2 CSP provisioning parameters are described here (http://msdn2.microsoft.com/en-us/library/bb737579.aspx)
Elosogrande7076 shows us how to provision a couple of email accounts below. To be safe, use GUID-GEN (http://www.guidgen.com/) to generate unique GUIDs. This is because duplicate GUIDs will cause undefined results on your device.
<wap-provisioningdoc>
<characteristic type="EMAIL2">
<characteristic type="{7B3D74EC-35D9-45e3-B8F3-E38F4B90D174}">
<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="Username" />
<parm name="AUTHNAME" value="login@gmail.com" />
<parm name="AUTHSECRET" value="password" />
<parm name="DOMAIN" value="" />
<parm name="REPLYADDR" value="login@gmail.com" />
<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="1" />
<parm name="SMTPALTAUTHNAME" value="login@gmail.com" />
<parm name="SMTPALTPASSWORD" value="password" />
<parm name="SMTPALTDOMAIN" value="smtp.gmail.com" />
</characteristic>
</characteristic>
<characteristic type="EMAIL2">
<characteristic type="{877e6100-cd6d-4a44-bd4c-3edf4b901480}">
<parm name="SERVICENAME" value="Gmail1" />
<parm name="SERVICETYPE" value="IMAP4" />
<parm name="INSERVER" value="imap.gmail.com" />
<parm name="OUTSERVER" value="smtp.gmail.com" />
<parm name="NAME" value="Username" />
<parm name="AUTHNAME" value="login1@gmail.com" />
<parm name="AUTHSECRET" value="password1" />
<parm name="DOMAIN" value="" />
<parm name="REPLYADDR" value="login1@gmail.com" />
<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="1" />
<parm name="SMTPALTAUTHNAME" value="login1@gmail.com" />
<parm name="SMTPALTPASSWORD" value="password1" />
<parm name="SMTPALTDOMAIN" value="smtp.gmail.com" />
</characteristic>
</characteristic>
</wap-provisioningdoc>