knowing how much scripting work has gone into this site, and the inevitable little problems that get thrown up, I can understand how easy it is to end up with errors in php.
The standard software out there, whatever version never has all the features an individual site would like, just the basic one fits all solution, and a certain level of modification will be needed. The modifications are rarely all written by one company/person, so never seem to quite get along with one another so you have to modify the modifications. Then when you install another modification, you have to revisit your original modifocation and modify it again...
When you get to a dozen or so modifications, it can become quite a headache beleive me.
Feel sorry for the chap doing the coding, as its probably been a bit of a ball ache to fix.