W97M/Mimir.A is an overwriting Word 97 macro virus with a mass mailing ability.
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.
When an infected document is opened, the virus will change the title of the Word's window to:
MiMiR is giving your computer new intelligence!
Then the virus ovewrites the three recently used documents as well as every file with ".doc" extension in the "C:" drive with the active document.
Finally it attempts to use Outlook to send a message to the every person listed in the "Contacts" folder. The body of these messages contains the following text:
Some nice jokes you got to read!! :))
The active document is attached to the message as well.
Technical Details: Sami Rautiainen, F-Secure