Gurunet says wrought comes from: [Middle English wroght, from Old English geworht, past participle of wyrcan, to work.]
Is work a weak verb? I have heard people speak of working metal, for ex., or that metal was worked. If I did some work, I worked. To me, wrought has more implication that something was created. Odd--does anyone actually say, today, that they (for ex.) wrought iron? I can only imagine someone saying they made wrought iron (wrought being an adjective here), or worked with wrought iron. Anything except that they wrought iron.