Cisco Clean Access, Minor Issue

Just noticed today that I couldn't send mail to the school's smtp server. Gave a call to the student help desk, as the email connection information had recently changed, just to be greated by Evan and he attempted to help me configure Thunderbird to send the mail, but it continued to refuse to send the mail. I disconnected from the wired network, and also Clean Access, and connected to the wireless network in Black Forest. After this, the email sent flawlessly. Connected back again to the wired, Clean Access, and once again, it refused to send (a test message).