Having Exchange 2003 work as a listserver for specific distribution lists?

I have been having a near impossible time trying to figure out if (A) There is someway to tweak or add a Microsoft supported plugin to exchange 2003 so I can create/manage newsletters or (B) find a legitimate 3rd party product that will do the job without becoming a full time job to maintain (i.e majordomo + sendmail)...

We basically send out a news email (2 to 3 times a day) to a group (distribution list) of 1500 addresses. These people have all requested to be on the list. This list is currently just a distribution list managed in exchange/active directory. However, it is very time consuming to manage it this way, as you can imagine. 3-4 people are being added/removed to it every day....  

I am looking to turn that specific distribution list on Exchange into a newsletter where there is an opt-in and opt-out option on the bottom of each email that is sent out to the list. You would think that this functionality would be built right into Exchange (as it is the king of all messaging) but I have had no luck finding a solution.

I found this website www.ikakura.com but only found 1 review for it after searching the net. There has to be something a bit more standard. Every major web site out there has newsletters.....  

How does Microsoft itself handle news letters? They have hundreds of opt-in/opt-out newsletters available...

Any suggestions/solutions would be appreciated.

Thanks.