I read messages log for... my personal entertainment...
and I found what could be a bug...
I have activated the virus scan of the emails from the server manager and...
Sep 7 03:14:06 server /etc/e-smith/web/functions/emailsettings[15387]: /home/e-smith/db/mailpatterns: OLD UmFyIRoHA=pattern|Body|UmFyIRoHA|Description|Rar archive (UmFyIRoHA)|Glob|yes|LineStart|yes|status|disabled
Sep 7 03:14:06 server /etc/e-smith/web/functions/emailsettings[15387]: /home/e-smith/db/mailpatterns: NEW UmFyIRoHA=pattern|Body|UmFyIRoHA|Description|Rar archive (UmFyIRoHA)|Glob|yes|LineStart|yes|Status|disabled|status|disabled
Perhaps in the configuration script there is an uppercase (or lowercase) to correct; I don't know where, but if someone shows me where to look, I can take a look too