When you're looking at the list of threads in any forum there is a column "last post: by mr.x" but when you click on the username it only links to the profile of the "last person" who posted, not the actual username you clicked on. So if you're looking at list and someone new has posted between the time when you loaded the page and when you clicked on their username then it clicking on the username "mr.x" takes you to the profile of "mrs.y" instead. This happened to me and I had to click it three times and then examine the link address in the status bar before I realized what the problem was.