Quick update on this.

I sent a mail to banned@slashdot.org on Thursday asking to be 'unbanned'.  No reply yet but the ban does seem to have been lifted...I'm getting the feed now.

Note to Nick Bradbury of FeedDemon: Agree my orginal posting title is misleading (My RSS Reader (FeedDemon) banned from Slashdot), but hopefully anyone else searching using this term to find a fix will find the entry and understand the actual proxy server  cause...thanks for the updates on your site since.