I am the Rednose on http://forums.comodo.com as well, and I am also a member of the Malware Research Group there. Not that I am a great Malware Researcher, but if I find something undetected I submit it
Maybe I can do the same for Avast! I found this on the knowledgebase :
you can send it in a password-protected zip file to virus@avast.com making sure the password is included in the body of the email.
The email procedure is correct, and if you are going to submit multiple samples that would be one way as the multiple samples could be contained in the password protected archive.
The other method, submitting from the avast chest - Up to a point that procedure is correct, you will notice that it is in the Infected Files section of the avast Chest and that only happens for files detected by avast so if avast doesn’t detect a file you would have to add it to the chest.
You can also add the file to the User Files (File, Add) section of the avast chest where it can do no harm and send it from there. A copy of the file/s will remain in the original location, so you will need to take further action and can remove/rename that.
Send it from the User Files section of the chest (select the file, right click, email to Alwil Software). It will be uploaded (not actually emailed) to avast when the next avast auto (or manual) update is done.
To avoid waiting for the next auto update, right click the avast ‘a’ icon, select Updating, iAVS Update. During the update check you should notice the file being uploaded. Periodically scan the file from inside Chest, after VPS updates, when it is no longer detected you can restore the file/ to their original location/s.
From the user files section it is possible to select multiple files to submit, however, as far as I'm aware the pop-up window (form you need to complete) to enter information on why you are sending the file, might have to be completed for each file.
I don't know if this process has been modified for multiple submissions.
I found this on the knowledgebase :