Actually, it would be kind of sweet if you could verify that the fix is working.
If you want, please do the following:
1. update avast to the latest build (4.5.561).
2. stop the Internet Mail provider
3. download
http://www2.asw.cz/~vlk/ashmaisv.zip and extract its contents (both files) to the avast folder.
4. restart the Internet Mail provider.
We'd be grateful if you could tell us if it solved the problem.
Thanks
Vlk