My sister works for network support for state of Texas. She doesn't send out warnings randomly so when I get one from her, I take it VERY seriously.
Copy of her email below:

We have discovered a new virus. It is called W32.Mimail.A@mm. Since this virus was just discovered TODAY, we are NOT protected against it yet. In order to fortify our email system quickly, we must make GroupWise unavailable from 12:30 until approximately 12:45. If you'd like more information regarding this virus, I will attach a link below.

Please exit GroupWise and GroupWise Notify by 12:30.

http://securityresponse.symantec.com/avcenter/venc/data/w32.mimail.a@mm.html

>>> Nancy Long 12:20:40 PM 8/1/03 >>>
We have a possible virus coming into our email system. Please refrain from opening zip files until we can verify that this in fact a virus.
So far, the subject line has been "your account". Please do NOT open the attachment until we can complete our research. Please note that if this IS a virus, the subject line can change.

Hopefully they will have a patch soon!