Email flagged as Junk/Spam

Most of our email have been flagged as Spam
Hotnail, AOL, and many major corp.
Gmail receives email ok

We have an exchange server,
I have called sbc to setup a PTR record for
email.bhccrane.com IP 206.171.90.242
My server dosnt seem to be an Open Relay

I am running out of ideas. Any suggestions?

Copy of resturned hotmail email: