Well before we talk about drinking old wine allow me to suggest a few things. With wine this old several steps are in order to increase the odds of having a good experience with the wine.
1. - Stand it up for several days before uncorking it.
2. - keep the wine cool, say 60F
3. - Assume the cork will desintegrate. Use an ah-so to remove the cork but add the extra protection of using the screw from a scewpull to secure the cork. Our friend illustrates the technique here http://www.youtube.com/watch?v=fBdgn3AlkYo
4. - Taste the wine when the cork is pulled, it will most likely seem shot, but maybe not. If it seems like burnt be patient, let the wine sit in the bottle for an hour or two, then check again. With slow oxygenation many an old wine has revived itself at least enough to give a glimpse of it's grandeur.
5. - when the wine seems ready to go very gently decant it off the sediment and serve.
Enjoy the wine, unless it's totally shot there is always something to learn from old wines. It's going to be delicate, and savory with acid showing and probably not much left in the way of tannin or fruit, but it should be complex and aromatic, earthy and damp with tobacco notes. Please let us know how it goes and we hope you get a great experience out fo the bottle!