See this wiki page.
This functionality has now been integrated into FA 2.4.x with the settings in the users table as the fields:
sticky_doc_date
transaction_days
save_report_selections
Make sure that the browser cache is cleared and the company's js_cache is also cleared. Logout and login again and see what gives. In the last case above, this user choice data are stored in cookies and you must have it enabled. The others store it in the session.
The function date_cells() is the one that sets the form element. There appears to be no mention of sticky_doc_date(), new_doc_date(), etc there to remember the dates. The _last_val attribute of the date cell should be set from the sticky value.
@joe: needs a check to extend it to search forms as well?