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(dot)Lawrence(at)anu(dot)edu(dot)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