cron job (php email) not working after server move

[tnet]

We have two cron jobs set up that send transactional emails and event reminders via two php scripts and exim. These have worked fine for 4 years without any issues.

We moved the account to a new server about 10 days ago, but didn't change the nameservers until last night.

When we first moved the account the cron was running fine, as we had duplicate emails that first day (one set from each server) then realized it and turned off the cron on the new server until we were ready to go live.

We then updated apache and php to the latest version and had a developer clean up the code in a few files in order to be able to handle it. The files that run the cron jobs were not touched.

We then changed the nameservers last night and went live. Everything works great, but the cron emails are not being sent. We have spent all day checking and double and triple checking everything to try to figure out why and can't find anything that's different that would cause this. Then at 2:30 pm I ran a cron restart (# /etc/init.d/crond restart) and a bunch of the emails shot out, which appeared to be all those that were expected today up to that point. Then at 3:15 a user payment triggered another one, right on time, as we were notified by paypal of the payment at the same time. Then nothing since. I have initiated numerous test transactions that should trigger emails and nothing. I have even tried restarting the cron again and nothing. I have checked mail in the que and they aren't there.

Does anyone have any idea why this might be happening and what we can do to fix it?

Thank you for your help.

[lijeeshsd]

Did you check if the cron jobs were stuck and found in process list?