Record Locking with SQL 2000 back end

Rather than have users be able to directly open the back end tables I have
forms with Datasheet views that allow the users to open the raw data in the
tables. Each form has one of the tables as its record source and has all
the fields on the form locked and the table has No additions, deletions,
edits, etc.

I have a problem with some of the larger tables where a user will open up
the datasheet form and keep it open. This ends up preventing other users
from editing data even though this person with the datasheet form is just
sitting on say record 150 while someone is trying to edit record 5000. Once
the datasheet form is closed, editing can proceed normally.

What can I do to allow users to see the full table of data, but stop this
from locking out other users.

SQL 2000 SP3 back end using Access 2003.