https://portal-plumprod.cgc.enbridge.com is an English site located in Ontario, Canada. The server uses a very weak (256-bit) Diffie-Hellman key for DHE_RSA SSL cipher suites. See 583337 comment 6 for the original report of this problem. To fix this server configuration problem, either - use a 1024-bit Diffie-Hellman key for the DHE_RSA SSL cipher suites, or - disable all DHE SSL cipher suites. The latter may be easier to do.
So... we seem to have no sane way to set blocking flags on TE bugs. Mike, Christian, do we need to move this to Core or something?
Multi-state blocking flags require us to (ugh, christ) patch bugzilla to apply to other products. Easiest thing to do is: file a new bug in Firefox::General, set that to blocking, set it to depend on this one, grimace.
https://portal-plumprod.cgc.enbridge.com has disabled all DHE SSL cipher suites. Marked the bug fixed.