setting MTU of a NIC

[Sebastian Stark <seb_(_at_)_gosh_(_dot_)_todesplanet_(_dot_)_de>]

In <Pine_(_dot_)_LNX_(_dot_)_4_(_dot_)_21_(_dot_)_0009151026340_(_dot_)_27961-100000_(_at_)_snuggles_(_dot_)_fuzz_(_dot_)_net_(_dot_)_au> Jason
Rennie said I had to set the MTU of all my NICs in the network to 1412 bytes
if I use DSL/PPPoE. Now that I try that I'm discovering some trouble...

  # ifconfig rl1 0.0.0.0 netmask 255.0.0.0 mtu
  ifconfig: 'mtu' requires argument

the mtu option seems to be implemented.

  # ifconfig rl1 0.0.0.0 netmask 255.0.0.0 mtu 1412
  ifconfig: SIOCSIFMTU: Invalid argument

I do not understand this one. It's the same in 2.7 as in 2.8. mickey@ commited
the mtu addition to ifconfig.c 1.32 Tue Apr 11 18:08:42 GMT 2000 and I wonder
if anyone tested it since it does not occure in the associated manpage.

any suggestions?

-- dmesg --
ne0 at pci0 dev 13 function 0 "Realtek 8029" rev 0x00: irq 7
ne0: address 00:e0:7d:7a:b3:38
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