Bombed - Trying to Recover - Need Advice

["Thomas H. George" <xyz@spininternet.com>]

Second Mailbox received 70 ms mail bombs per day for the past two days. 
It was used only for subscription to debian-user list and I was 
apparently unsubscribed - i.e. nothing received from user list.

Took following actions:

   Contacted ISP, had address of second mailbox cancelled  and new 
address  created.
   Subscribed to debian user list from new address.
   Ran clamscan -r -i --remove from root directory.  Clamscan removed 
Exploit.IFrame.Gen from Mozilla mail Trash box and Worm.Gibe.F from 
Mozilla Inbox.  (Note: I never opened any attachments to the mail.)
   Ran  chkrootkit.  Nothing found.

I never studied any of the postings regarding the ms mail bombs which I 
now regret.  I know there were a great many so now I don't know where 
best to pick up the thread.

For the record my box is testing with a 2.4.20 kernel on a wireless 
network behind a standard ipmasq firewall on a stable box with no 
xwindows installed.

I would appreciate any advice or suggestions to insure no repetition of 
this problem.