TwoHandedSword: Thinking of
The Mandarin, hm?
In fairness, this restriction kind of makes sense to me. One could always claim that the magical laws of that particular universe don't allow such close contact between similar items because of some sort of magical interference. It just seems like an oversight that this is never specifically spelled out anywhere.
Fever_Discordia: Still doesn't explain why infinity engine games only let you wear one non-magical treasure item ring to save inventory slots though!
The ability to use only one magical ring in a hand could be also explained by e.g. that they work only on index fingers (something to do with your blood circulation etc.), or that only one finger is the correct size for the ring etc. (then again, are all rings and all index fingers exactly the same size?).
What irritated me though is how it is not obvious which magical items can't be used together. Like now in Icewind Dale I have this nice cloak that give 2 bonus to AC and saving throws, and a ring that does the same. Yet, I don't seem to be able to use them with any of my characters, because they are wearing something else that prevents to wear those. What is it? The heck I know. With one character, it seems to be his non-magical(?) +1 plate armor, because if I remove it from him, suddenly he can wear either the cloak or the ring. But I don't want him to move around stripped without armor because it is freezing cold in Icewind Dale and it would look funny.
But then, I also have another cloak that gives bonus to AC and other things, and it apparently can be used freely by anyone, no matter what else they are wearing. Why these incoherent restrictions which (magical) items can be used together? It is not nice having to test each item separately on each character, and trying to juggle with party members' armors and items so that they all could use the maximum number of magical items.