Tarpitting occurs if for one of two reasons.
1) You establish a large number of email connections to the mail server in a short period of time. The email server temporarily will block the IP address (usually for a period of 10-15 minutes). To avoid tarpitting, simply limit the number of connections that you establish to the email server per 1 minute period. In our shared hosting environment, Tarpitting prevents any single email user from monopolizing server resources, so that everyone can enjoy reliable email server performance.
2) You are not using SMTP authentication and attempting to use the mail server as an "open relay". If the mail server sees this activity it will tarpit your IP as suspicious activity.
If you have been tarpitted by the EDTHosting.com email servers, there is no need to contact support. Tarpitting will automatically release in 15 minutes.