I would agree with you guys, proper credit should be delivered
You just answered to users..? Also, I would tend to think you should answer to users in the first place. As an administrator of any server, it's standard practice to stay involved and respond with the community that way you're aware of their ideas and opinions.
I think this was uncalled for Dave. I don't know you well enough to judge, but I think they handled the situation maturely. They responded nicely, and were simply saying proper credit was due: and by all means they were right. I think you should talk to them with respect, just as you wish to be "treated with respect". It is only fitting and just.