Creat an XML feed from a WordPress post

I have a client who needs to create an XML feed for listing his jobs on a job posting site. I’d like to set this up so that he enters the jobs into WordPress, since he wants to do that on his blog anyway, and then it generates the feed to the posting site (job-search-engine.com).

So in this case it seems like the post entry in WP almost needs to be a form, to make sure the exact info is given for the feed. Does that sound right? This is a bit out of my league, but I’d love to figure it out. Any advice?

Custom fields?

Thanks for any help.

Kim