MSO tags for Office 2007 ribbon with vb6

We have Office addins that were written in vb6 for Office 2000-2003. I am working on modifying them to include ribbon functionality for Office 2007. I have the code working in vb6 to add a new group for all my ribbon items, but I would like to place the buttons throughout the canned Microsoft groups (eg: Home, Insert, etc)

Here is a shot from my xml file:
<customUI xmlns="http://schemas.microsoft.com/office/2006/01/customui" >
<ribbon>
<tabs>
<tab idMSO="TabHome" >
<group id="MSOffice" insertAfterMSO="GroupClipboard" label="Office Functionality">
</group>
</tab>
</tabs>
</ribbon>
</customUI>

When I open an office app, I get this error:

The attribute 'idMSO' on the element '{http://schemas.microsoft.com/office/2006/01/customui}tab' is not defined in the DTD/Schema

As I said before, if I change idMSO to id and take out 'insertAfterMSO, and make my own tab everything then works fine. I was just wondering if anyone developing with vb6 and office 2007 has been able to use the MSO tags successfully??

Hopefully this all made sense......let me know if you would like some clarification.
Thanks

Well - figured it out and of course it was a dumb reason. The tags are case sensitive so you must use idMso instead of idMSO :( makes me sad.