If I select a thread that has Last Page, for instance the Comments on this site thread which lists "1 2 3 4 5 ... Last Page", and I click Last Page I am taken to a mostly blank white screen with no posts.
In the above case the numbering at the top is 1 2 3 4 5 6 7 8 9 10, yet to the left of those numbers it says Pg.11 of 10. To get to the actual last page of that thread I need to click the 10 at the top.
Below was later added to the above post:
As I normally use Netscape v4.7x out of curiosity I decided to try the above with Internet Explorer v5.0x. The Last Page that I was taken to had a post and worked fine. So it's a Netscape glitch (fortunately with a fairly simple workaround).