we were unable to determine exactly what caused the issue because shortly it was fixed.
We were able to determine that the mail would not resolve and sat in the send directory filling up untill disk space was full. we contacted people who determined that they had no requests from our servers through their switch so there was definitely a problem with the firewall or dns. I was unable to view the logs while this was occuring so i'm not sure of the exact errors. we have relay disabled so i'm thinking it atleast wasnt an attack, but i could be wrong. gwia is the only application that handles the smtp. which is hosted on another port other than 25 because of routing records, which i am not sure about.
thanks for the post though.