Automation of PDF Portfolio Package Collection management

Automation of PDF Portfolio/Package/Collection management

How can I automate handling of Portfolios?

PDF 1.7 introduced "portable collections" as a standard construct.
With Acrobat 8 and 9, these were exposed as "Packages" or "Portfolios",
respectively.  End-users are starting to experiment with them--that is,
*my* end-users are; I have no doubt early adopters were playing already
a couple of years ago.

I need to do lots of things with PDF images, automatically.  To start,
though, it is crucial that I be able simply to diagnose which images
are portfolios.  "Simple" for me means something like, "there's an
Ubuntu package available now that you can invoke from the command line
to report ..."  "Fire up Acrobat, click on ..." does NOT qualify for
me as "simple".  I welcome any ideas, though, that admit adaptation to
automation under Linux.

Ten minutes of trying to read the PDF image directly and detect
"portfolioness" foundered on my ... inexperience with the PDF standard.
I'm sure I could eventually write what I need, but I'd prefer re-using
what someone else has already done.

pdftk has interesting capabilities.  I e-mailed Sid Steward last week
asking if he had any plans to accomodate portable collections; I've
seen no response.

iText apparently understands portable collections in recent (for a
couple of years) releases <URL:
http://www.lowagie.com/itextwiki/doku.php/collections >.  While
Java coding isn't a *problem*, working out deployment details again
will require more time than I prefer to invest at this stage.

If no one knows an answer that's at most one step removed from the 
Linux command-line (I consider iText, as currently documented, two
away--and Acrobat about nine), I'll start coding my own iText-based
utilities in Java.  Anyone have any experience with the iText group? 
Do contributions from outsiders interest them?