office:value-type in boolean cells

Hey,

so going through our validation errors in calc I found an interesting issue.

If you have a cell that returns or contains a value and format the cell as
boolean we export the value-type as boolean and the boolean-value as the
value of the (formula) cell.

Now obviously this generates invalid files as the boolean-value attribute
only accepts true and false. However looking further into the file format
spec it seems that this case is actually totally buggy in ODF itself as if
you export correct files you loose the information about the cell value.

As a simple example:

          <table:table-cell table:style-name="ce2"
office:value-type="boolean" office:boolean-value="4"
calcext:value-type="boolean">
            <text:p>TRUE</text:p>
          </table:table-cell>

Obviously if we replace the office:boolean-value with "true" as mandated by
the spec the file will not carry the information that the cell actually is
a 4.

I might have missed something fundamental here but after reading the spec I
think that there is a big flaw in the spec and we can't use the boolean
value-type for cells formatted as boolean. Can you please double check as I
surprised that such a big error in the spec has not been noticed for a long
time.

Regards,
Markus