tuple size too big??

I am connecting to postgres 6.4.2 on rh linux 5.2, using new kernel 2.2.2,
from access97 on a win98 machine through an obdc driver (somehow, that was
a mouthful!).  I am converting some access files into postgres.  One file
in particular has a NOTES field in it (access memo datatype, postgres text
datatype) that may have large amounts of data in various records.  When I
run an insert query to insert into the postgres tables from the access
table, it bombs when it hits a record with"too much data" - I get the error
message "tuple size too big, size 8360".  In the obdc driver, I tried
increasing the "text as longvarchar" amount to 15000 - no good.  I then
tried just unchecking the "text as longvarchar" option - no good.  I think
the message is coming from postgres, not the obdc driver.  I have found a
record in particular that causes the problem.  When I remove a few lines
from the data, it pulls in just fine.  The few lines I removed had no
special characters, etc.  what to do??  I need to be able to store this
data in its entirety.  How to increase the allowable "tuple" size?  What is
a tuple anyway??

jt