Mail server IP blocked

all these black lists shall be forbidden by law!

[idolw]

We have about 30 people steadily sending out e-mails with offers to our customers, who requested our services first.
As we sell, all our e-mails contain the spam-like words, such as: buy, credit card, money, confirm.

Our mail server IP got on plenty of these shady anti-spam lists run by micro companies or even single guys who want to become heros.
These comapnies have websites that look like no one updated thenm since 14th century.
I really do not understand the reasons to for this all happening.

Is changing IP of the mail server is the only way to avoid these problems?

[topsites]

owner edit lol