After having some corks dry out on early batches, I have since then always stored mine on their sides and have perhaps been lucky not to have cork 'taint'.
In any case, these days, I am using the new plastic corks which are superior to natural corks. I also use screw top wine bottles when I can get them. They are the ideal and most sensible closure for wine anyway. It's nice to see some high quality wines in the stores these days sporting the handy screw tops.