Communication Autocad -> Delphi

I have read a lot of articles about Delphi and AutoCAD automation. But
most of them are over the communication (sending commands) to AutoCAD
(OLE). I tried this and this works fine. But I can't find anything
about the communication from AutoCAD to Delphi.

I have an AutoCAD drawing with certain points, al these points are also
in an access database with additional information. I made a link with
AutoCAD and the access database, this works fine. And I made a link
with my Delphi program and the same database. So I can edit and
calculate values in the database with my Delphi program. If I select
certain points in my Delphi program I can send a command to AutoCAD to
zoom in on these points. This also works fine.

Now I want to make a link between AutoCAD -> Delphi. I want to make the
following thing: If I select one ore more points in the AutoCAD drawing
and for example send a command. Then I want to receive the coordinates
or name of the points that are selected in the drawing. So I can select
(or highlight or display) the selected points in the Delphi program.

Does someone have experience with this?

Thanx for the effort!!

Additional info:
Autocad 2005
Delphi 7