"Submit"ting shows a blank page instead of showing the thread

Here is another thread which has started to show this problem:
http://www.amigans.net/modules/xforum ... e=&order=ASC&type=&mode=0

Clicking on post #60 goes to a blank page, but #59 & lower work just fine.

Here is the bad link for post #60:
http://www.amigans.net/modules/xforum ... id=102628#forumpost102628

And this is the (slightly different) bad link that I received after making post #60:
http://www.amigans.net/modules/xforum ... id=102628#forumpost102628

I can "trick" the website to do what I want, using the following URL:
http://www.amigans.net/modules/xforum ... id=102623#forumpost102628

But this only works because "post_id" is for an older post on the same page, and "#forumpost" doesn't determine the page sent to the browser, it's only used by the browser after it receives the page.

So for whatever reason "post_id" fails to find the correct page of some posts.


I checked what happens after 60 posts on a different problematic thread, and something interesting happens. I can jump to post #59 just fine:
http://www.amigans.net/modules/xforum ... t_id=86774#forumpost86774

But trying to jump to post #60 takes me to the WRONG page:
http://www.amigans.net/modules/xforum ... t_id=86777#forumpost86777

It therefore seems that after 60 posts "post_id" becomes unreliable at mapping the post to the correct page. In the case of blank pages we've seen, it is no-doubt trying to send us to a page that doesn't even exist.


Given that SOME sub-forums threads wrap to a new page after 20 posts (i.e. the 21st post is on the next page), while on the Odyssey thread it wraps after 22 posts, it seems oddly suspicious that the problem (can) happen on the 60th post (i.e. just before it should switch to the next page). This may or may not help identify where the bug is in the code.

e.g. Maybe it is confused about how many posts there are per page, and this leads it to calculate a different page than what the post is actually on. In the case of the (very long) problematic Odyssey thread, it may be trying to display a page that doesn't yet exist!

e.g. Or it may be 'correct' about how many posts there SHOULD be per page, but the website is actually displaying the incorrect number of posts per page! Some evidence for this can be found with this link:
http://www.amigans.net/modules/xforum ... hp?start=20&topic_id=6329

It is the link for the 2nd page of the problematic Odyssey thread, and you can see that it asks for "start=20" (the next page would be "start=40")... HOWEVER, what actually happens is that it shows posts starting from #23 !