large objects & space usage

Hi List;

I'm engaging with a client who is trying to solve what sounds like a bloat
issue. However in further conversations they told me this:

1) we have a table that is an integer key and a blob column
2) the table was at 30Gig, we went in and deleted the last 2 months of data
and it's still at 30Gog

At this point I thought bloat and that vacuum full or a table rebuild would
fix the issue.  However later they told me:

3) we did a pg_dump and a reload into a database on the test box and the table
is still 30Gig.

I haven't gotten access to their servers yet so I only have the above info
however I wonder is there special space considerations or storage
requirements, etc with blobs ?

Thanks in advance...

/Kevin