Recent replies feed

Is there any way that I could generate a feed that shows the 15 most recent posts in a specific forum but excludes the first post of each topic? I'm trying to use punbb as a commenting system on my WordPress blog. I've got it set up so that each blog post creates a new topic in my "Blog Posts" forum, and the comment link redirect to the corresponding thread. The reason that I want to exclude the first post but include all the others is so that I can set up a recent comments feed.