[pdftex] pop-up annotations

[ivo welch]

dear pdftex wizards:  I am trying to figure out how to make pop-up text
annotations that look similar to those that adobe acrobat (6.0)
creates.  they have sort of a speechbubble appearance (although I would
not mind my own little png image here), and when one clicks on them, a
yellow box with a relatively small outline, and some options with it.  I
have searched the pdftex documentation for "annotations" and "pop-up",
as well as some other search tools, but I could not figure out where I
could find it.

of course, I would be really happy if I could make the whole box 50%
transparent (almost surely not possible), and when the document opens,
have the note opened already.

could someone please point me to a few annotation examples with pdftex?

regards, /iaw