Duplicate ID error when clicking 'edit primary links'

On a brand new HEAD install from ~30 minutes ago, I clicked the 'edit primary links' link at the top of Bluemarine and was taken to the administer >> menu page with the following error:

Duplicate entry '2' for key 1 query: INSERT INTO menu (mid, pid, path, title, description, weight, type) VALUES (2, 16, 'admin/block', 'blocks', '', 0, 22) in includes/database.mysql.inc on line 108.

Subsequent clicks on this link just take me back with no error.

There is already a command in database.mysql to add these in:

INSERT INTO menu VALUES (2, 0, '', 'Primary links', '', 0, 115);

So probably either that line should be removed from database.mysql, or wherever it's adding the record in Drupal should first check and see if it exists.

I tried looking briefly but couldn't find where this was, though it's probably an easy fix for someone 'in the know' :)