[Exim] Whitelisting in Exim?

Hi Folks.

I know less than a newbie. My domain (InspiredCode.net) is hosted by
ipowerweb.com and the deal comes with business email service. Last
month, ipowerweb implemented new security patches on their server end.
They are now using Exim to block (not merely tag) mail according to
the SpamCop database. I am now missing credit card orders from my
shoping cart provider, who uses compuserve, because SpamCop has listed
their local group of IP as containing a spammer. My credit card
processing company (nstarsolutions.com) has never spammed and never
would. Can anyone send me detailed instructions I can pass on to
ipowerweb's technical support as to how they can configure their Exim to
whitelist nstarsolutions.com, or even how to quit filtering all mail
headed for me? As I see it, there are three things they could do:

1. Completely quit filtering just the mail headed for me.
2. Exempt nstarsolutions.com from blocking; white list them somehow.
3. Change the system to tag instead of block suspected email.

Depending upon what they are willing to do, I need to be able to
advise them as to how to do each of these three things. Can anyone
advise? Please send detailed instructions to: 1@???

Even if I don't understand what you send, I'm sure that they will.

: )

Many, many thanks in advance.

Robison Bryan
InspiredCode.net