F5/LineRate did it but it got NACKed in a fairly underhanded and unfortunate way on the mailing lists :/ https://github.com/Seb-LineRate/freebsd/commits/seb/stable-1...
The only mailing list thread I see regarding this is here, and it doesn't seem particularly underhanded to me: https://lists.freebsd.org/pipermail/freebsd-hackers/2014-Nov...
https://lists.freebsd.org/pipermail/freebsd-hackers/2014-Nov...
But maybe I'm missing something?
See also: https://lists.freebsd.org/pipermail/freebsd-hackers/2013-Sep...