I also did, and I also wasn't able to access gnuplot.info, maybe there is a prob...

edwintorok · on July 16, 2015

gnuplot.info works for me on IPv6 but not on IPv4 (get connection reset on IPv4), seems to be a problem with projects.sourceforge.net.

  gnuplot.info has address 216.34.181.96
  gnuplot.info has IPv6 address 2001:468:c80:a202:0:b074:0:c082
  96.181.34.216.in-addr.arpa. 3567 IN	PTR	projects.sourceforge.net.

This site has a different IP and seems to point to a DNS server/proxy:

  simongrondin.name has address 176.58.120.112
  112.120.58.176.in-addr.arpa. 85642 IN	PTR	unblock.us.org.

Edit: .name site works now