[XeTeX] xdvipdfmx and PDF/A requirements

[Dino Petrucci]

I was not able to find anything about xdvipdfmx and PDF/A. For me, there are 
two problems, at least, I can't solve:

1. the driver doesn't create the /ID tag in the PDF trailer, which is 
mandatory for PDF/A (this can't be done in a TeX document);

2. the driver always changes PDF Info's Producer (e.g. "xdvipdfmx (0.7.8)"), 
but this is a problem with XMP schemas (that are built in a Xe[La]TeX document 
and, therefore, should be independent of the driver version).

These problems have been solved in pdfTeX but not in (x)dvipdfmx, I think.
Thanks.

Dino Petrucci