Large object - what's happening?

Hi,

I decided how to deal with my large objects, and now I'm trying to get
them going in a python script.

I'm using pygresql. Is this considered a good thing? Should I use
something else? The syntax looks so simple - just  loimport(filename)

I get a python error:
_pg.err: can't create large object

In the postmaster log is a one-liner:
ERROR:  lo_lseek: invalid large obj descriptor (0)

Maybe I'm calling it wrong. Maybe I need to upgrade from 7.2.1 to
7.3.x?  Maybe I need a new book - Practical Postgresql is very light on
discussion of large objects, and is based on 7.1 or so.

Any clues? Pointers to documents?

thanks
Cath
Cath Lawrence,                       Cath.Lawrence@anu.edu.au
Senior Scientific Programmer,  Centre for Bioinformation Science,
John Curtin School of Medical Research (room 4088)
Australian National University,  Canberra ACT 0200
ph: (02) 61257959   mobile: 0421-902694   fax: (02) 61252595