Massive Spamming Problems

[XTJ7]

I've got massive spamming problems, is there maybe an problem with the internal mailer, a security leach so that spammers can access the sendmail protocol?
I've got many Problems with that, but i don't know what it is on my Server, i haven't installed any formmailers, nothing is there, but the spamming won't stop. Please give no comments like "close the accounts" or something like that, i need them. Changing the Password is not what i want, that are many accounts and anyway an hacker must be on the server, because out from my ftp Server i'm not allowed to access the dirs of the other users. But he/them is/are accessing these directorys in any way, not exactly accessing them, but the mail accounts. Don't know how, but i'm sure they don't even Hacked the Server... it's more. Please just answer this question, i don't want more support, i think i can get the hacker away, but if they come back, is it the YaBB SE? I've got 2 running on my server over different MySQL Databases.

Thats all for now, i just want to know if there is a way to access the internal form mailer.

cya!

[Jeff Lewis]

No, are you sure you don't have formmail.pl on your system somewhere?

But no they can't access the internal mailer through SE.