Thread:Extension talk:Favorites/Keep adding date on page move

I added a table column "fl_added" to store the timestamp when the user added a page to his favorites (lets me sort favorites by adding date, quite useful). Unfortunatly, on page move the date is renewed too and it looks like the page was added to favorites recently while it was just renamed.

I found moveToFav and it looks like the entry is deleted and replaced by a new one. How could I keep the row (and with it the original "fl_added" and only replace the old title with the new title?