How to block mail if Return-Path: and From: are not same

[sadiq007]

to avoid spam i want block mail for which Return-Path: and From: are not same.how can i do that?

because we are getting spam mail for our our users with sent address of our domain but with different Return-Path:
so i want block such kind of mails....

another is there any way to block mail which having perticular word in there subject or body ...for all users.
for example i want all mail which containing word "******" in there subject or body part for my all users.

[uxbod]

Spamassassin - check return-path against from address

[sadiq007]

hi UX,
As per your suggested link i am going to download script from Perl | package FromNotReturnPath; us - Ivan Korotkov - 0m9CYxzV - Pastebin.com
as there is no plugin folder in /spamassassin so i am going to create it , and will save this script as FromNotReturnPath.pm then i will add following lines in to /opt/zimbra/conf/spamassassin/newpre.pre
loadplugin FromNotReturnPath plugins/FromNotReturnPath.pm
header FROM_NOT_RETURN_PATH eval:check_for_from_not_return_path()
describe FROM_NOT_RETURN_PATH From: does not match Return-path:
then i will do following changes in salocal.cf
header __FROM_MYDOMAIN From =~ /\@MYDOMAIN\.com/i
meta FAKE_MYDOMAIN_ANNOUNCE (__FROM_MYDOMAIN && FROM_NOT_RETURN_PATH)
describe FAKE_MYDOMAIN_ANNOUNCE Fake mail from MYDOMAIN account management

score FAKE_MYDOMAIN_ANNOUNCE 40.0

Plz correct me if i am wrong anywhere..

BUT Ivan in that forum saying-
I'd recommend using it in conjunction with spamming domain (because, technically, return-path does not always equal From even in legitimate e-mail; maillists are counter-example).

So it means this rules will apply to all mails which are coming to my mail server and there Return-path and From address are not same...if this is right then as per him it will create problem incase of mails are from known mailing-lists

So is it possible that this rule will apply to only for my domain only, i mean if the mail have from-path of my domain and not having return-path of my domain then and then only it will be apply.