Hi lincemiope. The English language is strange. Most of the entries have taken the meaning of the word "vintage" to be something classic, or just plain old, but the primary meaning of the word is actually all about wine. I know that English is not your first language, so here is the definition:
1.the wine from a particular harvest or crop.
2.the annual produce of the grape harvest, especially with reference to the wine obtained.
3.an exceptionally fine wine from the crop of a good year.
4.the time of gathering grapes, or of winemaking.
5.the act or process of producing wine; winemaking.
6.the class of a dated object with reference to era of production or use: a hat of last year's vintage.

You are not the first one who has thought that the #6 definition was the only correct one.

Thanks photogirl. I happened to be in the law business.

Thanks BeSea. That knife dates from WWII. It was the famous "Fairbairn-Sykes, F-S fighting knife" developed by William Ewart Fairbairn and Eric Anthony Sykes in Shanghai based on concepts which the two men initiated before World War II while serving on the Shanghai Municipal Police in pre-war China, and made famous during World War II when issued to British Commandos, thus it was the very first so-called "commando knife"