In the case of linear codes, this is the same as asking for non-equivalent codes with the same weight enumerator. There are many examples known. Search for "same weight enumerator" at google scholar and you'll find some examples quickly. For example, [this paper][1] and [this one][2] and [this one][3] and [this one][4]. [1]: http://www.springerlink.com/content/hj40064667223702/ [2]: http://www.win.tue.nl/~ruudp/paper/57.pdf [3]: http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=748461&url=http%253A%252F%252Fieeexplore.ieee.org%252Fxpls%252Fabs_all.jsp%253Farnumber%253D748461 [4]: http://arxiv.org/pdf/math.CO/9310227