PDF/A-1a?

Andy Robinson wrote:
> Some changes to internal structures might be needed to issue
> ISO-standard PDF 1.7.  The problem is that lots of people
> would instantly assume we support everything which is possible
> in PDF 1.7, which would need hundreds of man-years of development
> :-(

A bit OT, but while we are on the subject:
Would it be possible to create PDF/A-1b or even PDF/A-1a with RL?

For PDF/A-1a, the tricky part is to create "tagged PDF", I think...

Has anyone on this list experience on this field - not necessary using RL?

One of our clients would like to create PDF/A-1a, however our framework,
(based on Eclipse BIRT) does not support this.
So I thought it could be possible to create a BIRT-patch to support this,
and I tried to understand the PDF 1.7 specification regarding this topic, 
but I'm a bit lost.

I need a good starting point from a developer's perspective.

Henning