Keep in mind that having multiple media files in PodPress is problematic for your podcast feed. iTunes will download the first enclosure that it sees in the feed ignoring the rest. Other podcatchers and podcasting directories either pick up the first enclosure or the last in each post item.
If you are doing this to organize your episodes into, for example, 3 segments, keep in mind that someone listening on iTunes is going to only listen to the first segment and someone using Google Reader is only going to get the last segment. Your almost never going to find anyone downloading the middle segment. If this is what you're trying to do, I highly recommend you confirm this problem on your own by subscribing to your podcast in iTunes, Google Reader, and other podcatchers to see that we're right.
If you are doing this to provide multiple formats of your episodes for example in mp3, m4a and ogg, we have a much better feature for that in PowerPrss called "Custom Podcast Channels". Podcast Channels allow you to provide separate feeds for each media type, and add additional podcast episode boxes to your edit blog post pages. Your separate feeds could look like the following: example.com/feed/podcast/ for your default mp3 media (example.com/feed/podcast/ is the default channel powerpress is packaged with), example.com/feed/ogg/ for your ogg version, and example.com/feed/m4a/ for your m4a version. Then your Linux minded listenres will want to subscribe to the ogg version, your Apple listeners would prefer the m4a version, and your users who just want the media to play on their media player or in their web browser though Google reader will appreciate the mp3 format.