Visualization of structure (OT?)

Hi all!

This might be off topic, my apoligies if my question's misdirected.

I'm looking for a way to visualize tha tables within a given database,
pretty much the way BlueJ (www.bluej.org - doesn't play well with
JDK1.4) shows sub- and superclass relationships. Have anyone seen
anything like this (freeware that is - numerous propietary solutions
exist for MS SQL etc.)? Most preferably I'd like to parse CREATE
clauses, to be able to parse/extract external keys and display that
correctly. I guess I will have to do it myself - and I probably will
since I'm fed up using xfig (vector based graphical tool). Nothing wrong
with xfig, but it's not designed to be used for this.
     As far as I've understood - all information that's needed to make a
complete graph/schema of the relations can't be extracted with the
jdbc-driver provided from jdbc.postgresql.org. Is this true?

Thanks in advance,

     Fredrik

PS. On-screen visualization is the primary target, PostScript generation
comes second. DS