This official news post is from before the launch of Old School RuneScape and is copied verbatim from the RuneScape website. It is copyrighted by Jagex. It was added on 28 May2001.
I have add a new button to the stats menu which shows you which of the 15 quests you have completed. I hope this proves useful to people who are trying to work out which ones they have missed, so they can complete them all!