1. mirrors.rcn.net is one host, no matter if it's accessed on port 21 or 80 (well, the other possibility isn't very likely), so having it in MASTER_SITE_SOURCEWARE twice doesn't make much sense. 2. ftp://mirrors.rcn.net/mirrors/sources.redhat.com/%SUBDIR%/ fails for every MASTER_SITE_SOURCEWARE using port I checked, while {ht,f}tp://mirrors.rcn.net/pub/sourceware/%SUBDIR%/ does have the tarball.
State Changed From-To: open->closed Variation on your patch committed. Ad point (1): it's nice to have at least one http host in mirror list.