PMTU discovery?

[Val Smith]

Hi,

I have a quick question and hope it isn't too
newb :)

Does FBSD support PMTU discovery on ethernet
interfaces and, if so, how is it enabled? I've
looked in the man pages for both ifconfig and xl
but could only seem to find reference to manually
setting MTU, not autodiscovery. I know how to set
this with windows registry but want it for a FBSD
5.1 workstation as well.

TIA,

VS