It's been such an oft-wished for thing, and I myself as a player have long said I would welcome it for my characters... so as of now, you can now equip TWO rings.
Be aware however, that you can only equip ONE ring with stats at any one time. The second must be purely decorative.
The rings that you can now equip in addition to a ring with stats are these:
Silver Ring
Golden Ring
White Gold Ring
Garnet Ring
Diamond Ring
Promise Ring
Ring of Hope
Friendship Ring
(and any other decorative rings that may be added to the game in the future.)
The other thing to note is that this will only apply to rings produced as of the time of this post. Any rings already in existence will not be able to be equipped in this manner.
IF however you have a special ring that you would like to wear, and don't want to just go and get another one - rings with sentiment attached, or gifts from gods - then you can PM me at character 24 and I will work some magic on them. As long as I don't get deluged with requests, that is. I'd appreciate you telling me WHY you can't just go and get another ring instead as well, so that I know you're not just being difficult.
Enjoy.
M.