Cannot perform date calculation

[CoLdFuSiOn]

YaBB SE Version: 1.5.3
PHP Version: 4.3.1
MySQL Version: 3.23.x
Server Platform: Windows
Link to Forum:

Problem Description:
I've just converted my board from YaBB Gold (perl) to YaBBSE and evrything went pretty well, and as far as I can see everything is working as it should. However, there is one tiny problem, just a couple of people are saying that they get an error opening some threads. I checked the forum error log and found the following...

/yabbse/index.php?board=1;action=display;threadid=4;start=0#lastPost
2: Cannot perform date calculation <br />(c:\apache\Apache\htdocs\yabbse\Sources\Subs.php ln 377)

Anyone have any ideas why this is happening on only a few threads and only for some users? also of course, how to fix it!

Thanks in advance

[[Unknown]]

You might try checking the database for negative values in the posterTime field....

-[Unknown]