Having same problem. Spamcop is blocking as well. Interestingly - mail sent to outside address is going through to many of them, but mail sent to other domains under my reseller account are being blocked. I have explicitly disabled spam filtering for some of these recipient addresses on Jodohost...
Getting a variety of errors - 554 and 521 when trying to send email to aol.com addresses.
554 5.2.1 Email fails this check...decline
521 5.2.1 Email fails this check...decline
Its not my domains - the mail goes through if I route it differently. Only mail that is relayed through Jodohost...
Spamcop blacklisted this SMTP server today - specifically the IP 173.0.136.173. Since it is a shared resource, it is difficult to remove the blacklisting without it being re-added.
I'm on cluster2 - all my domains are down, not even resolving dns. All mail down. I attempted to call, but got hung up on, been waiting for live chat for a while. No access to control panel.
Even thought it was posted otherwise on the status thread, given the length of the outage, mail sent to domains on mail3 is now bouncing back to the original senders. This just keeps getting worse.
mail3 has the heaviest of my mail users. I know full well the issues of rebuilding a server and restoring a backup, but without the control panel, I also don't have the option of redirecting the mail for those domains even temporarily. Any suggestions?
As an additional note, if your .htaccess entries do not appear to work, make sure that there is only a single space between the variable and the value, from a response on the Drupal site:
This worked for me solving the mbstring issue