What's happened to the word 'renowned'?

Lately I've noticed people using the word renown as an adjective. Here's an example from The Age newspaper today:

A western suburbs real estate agent who rorted more than $156,000 from the ANZ bank in a property scam has asked for his licence not to be revoked - on the novel grounds that he is an internationally renown accordion player who often performs for charity. 

I've been mystified as to why such a strange mistake would arise. At first I thought it was a typo, but I've seen it too often for that to be the case.

To me it's weird. After all, I would think the word renowned is an adjective, formed from a past participle. I can't see why you might insert a noun where the structure of the sentence calls for  an adjective.

But when I think about it, I don't know any verb 'to renown' or 'to renow'. So I looked around the Net.

A discussion at wordreference.com suggests that people may be comparing 'renown' with known (which has me wondering how they pronounce it).

  The Online Etymology Dictionary says:

c.1300, from Anglo-Fr. renoun, O.Fr. renon, from renomer "make famous," from re- "repeatedly" + nomer "to name," from L. nominare "to name." The M.E. verb renown has been assimilated to the noun via renowned "famous, celebrated" (late 14c.).

If it's a verb, I suppose it's transitive, so you might say, His fans renowned him. (They named him repeatedly.)

After all that thinking, I've come to the conclusion that I still think the sentence in today's Age newspaper should have said, '...that he is an internationally renowned accordion player.'