Where does it say magic-users can't cast spells in armor?

[Zulgyan]

I was studying the way M&M describes the classes, and nowhere does it say that magic-users can't wear armor, or that they can't cast spells in armor. I just says: "Magic-Users may arm themselves with daggers only". That refers to the weapons they may use, but not the armor. In the spell section of the booklet, no reference is made with regards to armor and casting.

Not pretending to say I'm making some sort of revisionist discovery, as it is well known that the magic user's none use of armor was implied in the rules (in the Elf description it says: "They may use magic armor and still act as Magic-Users").

When was the first time this issue was specifically addressed or clarified?

Any thoughts?

[foxroe]

It's in the preceding clause of that sentence: "The whole plethora of enchanted items lies at the magic-users beck and call, save the arms and armor of the fighters (see, however, Elves)..."

It's generally accepted that these references to magic armor and weapons also apply to the non-magical varieties. Otherwise, Clerics can only wear magical armor, and are allowed the use of non-magical edged weapons.