Assuming you mean flag a file to be missed during a scan. On the home products that isn't possible at the present time. We have asked for it, however.
If VirusScan is mis-identifying something as malware then forward it to Avert Labs.
Send a file to Avert for analysis:http://vil.nai.com/vil/submit-sample.aspx
Email file to: email@example.com
When submitting samples via E-mail all samples must be packaged in a .ZIP file. When creating this .ZIP file, it is important to understand that the .ZIP can be no more than 3 megabytes in size and can contain no more than 30 files. Additionally, any .ZIP file created must be password-protected using the password "infected" (minus the ""). Failure to follow these guidelines will cause your submission to be rejected.