Amit Bhatt wrote:
we are receiving around 1000 spam E-mails on a daily basis via one of our mailing lists. Most of these spams are received in form of subscription requests. The spam appearing in a huge scale is badly effecting the performance of the list. Would appreciate if anyone can suggest us the proper remedies to resolve this issue.
You should use tools like spamassassin, clamav (with 3rd party signatures such as those from http://www.sanesecurity.com/), etc. in your incoming MTA to stop spam at the front door. Once it get's delivered to a Mailman list-subscribe or list-join address, it's too late.