I've created a cab file to set up most of the info needed for push activesync and it works fine on a jasjar and on a k-jam, but fails on an HP 6915 - it appears that the XML model in the 6915 is different. The HP6915 claims to be running AKU2.3 (which is later than the the jasjar and k-jam, but I can't find any info on what has changed in wap-provisioningdoc. As the HP device is with a user, I can't easily try lots of variations.
<wap-provisioningdoc>
<characteristic type="Sync">
<characteristic type="Connection">
<parm name="Server" value="mail.mysite.com"/>
<parm name="AllowSSLOption" value="1" />
<parm name="Domain" value="mysite.com" />
</characteristic>
<characteristic type="Settings">
<parm name="BodyTruncation" value="5120"/>
</characteristic>
<characteristic type="Mail">
<parm name="Enabled" value="1"/>
<parm name="MailBodyTruncation" value="5120"/>
<parm name="MailFileAttachments" value="0"/>
<parm name="EmailAgeFilter" value="4"/>
</characteristic>
<characteristic type="FolderHierarchy">
<characteristic type="Sent Items">
<parm name="SyncEnabled" value="1"/>
</characteristic>
</characteristic>
<characteristic type="Calendar">
<parm name="Enabled" value="1"/>
</characteristic>
<characteristic type="Contacts">
<parm name="Enabled" value="1"/>
</characteristic>
</characteristic>
</wap-provisioningdoc>