Hi, thanks for everyone's help and information. This frame has me confused and I'm seriously doubting the past history as a Colnago. I believe that it isn't a frame actually manufactured in Ernesto Colnago's workshops. Whether he had these frames made for him by other manufacturers, I wouldn't know but Legnano "influence" on this frame is evident - in my humble opinion. After all, Maffioletti frames were made by Bianchi in the good old days.
Therefore I have decided to sell this frame and it is now [2 Jan. 2011] offered on eBay UK and eBay, item no. 160526392508.
Best wishes to all for 2011.