I'm beginning to think this server is supernaturally possessed.
I ported a site to a different server. Now, trying to submit a long post it returns an unnamed server error.
Even if I exit at the beginning of the script before the data is processed and added to the database it still returns this error. So I don't think its database related.
Here's where it gets weird. When I remove every occurrence of the word 'from' from the bottom third of the text it submits fine. The word 'from' appears at the top of the text a number of times.