Question : cannot email hotmail

We have exchange 2003 on a sbs server sp2.  Verizon Fios is our ISP.  For some reason we cannot send email to hotmail.  I can reply to a hotmail message and I receive from hotmail but I cannot send to a hotmail account.  I can also telnet mail.hotmail.com 25 and I tried the smtp connector outgoing.verizon.net.  How can I fix this?

Answer : cannot email hotmail

I found out hotmail blacklisted us for some reason.  I put in a request for hotmail to remove us from their blacklist, and I will see how it goes