It works fine in 1.6.2 and 2.0RC4.  But AFAICT -current drops half the 
packets.  This is on a PowerMacintosh 7300.

Any further info I should include when I file a PR?

   -- MW

mc0 at obio0 offset 0x11000: irq 14,2,3: address 00:05:02:2e:2e:54

PING server (10.0.1.2): 56 data bytes
64 bytes from 10.0.1.2: icmp_seq=0 ttl=255 time=0.921 ms
64 bytes from 10.0.1.2: icmp_seq=3 ttl=255 time=1.058 ms
64 bytes from 10.0.1.2: icmp_seq=4 ttl=255 time=0.979 ms
64 bytes from 10.0.1.2: icmp_seq=7 ttl=255 time=0.914 ms
64 bytes from 10.0.1.2: icmp_seq=8 ttl=255 time=1.015 ms
64 bytes from 10.0.1.2: icmp_seq=11 ttl=255 time=0.948 ms
64 bytes from 10.0.1.2: icmp_seq=12 ttl=255 time=0.944 ms
64 bytes from 10.0.1.2: icmp_seq=14 ttl=255 time=0.938 ms
64 bytes from 10.0.1.2: icmp_seq=15 ttl=255 time=0.964 ms
64 bytes from 10.0.1.2: icmp_seq=18 ttl=255 time=0.991 ms
64 bytes from 10.0.1.2: icmp_seq=19 ttl=255 time=0.955 ms
64 bytes from 10.0.1.2: icmp_seq=22 ttl=255 time=0.898 ms
64 bytes from 10.0.1.2: icmp_seq=23 ttl=255 time=1.007 ms
64 bytes from 10.0.1.2: icmp_seq=26 ttl=255 time=0.896 ms
64 bytes from 10.0.1.2: icmp_seq=27 ttl=255 time=0.915 ms
64 bytes from 10.0.1.2: icmp_seq=30 ttl=255 time=0.907 ms
[...]
----server PING Statistics----
244 packets transmitted, 119 packets received, 51.2% packet loss
round-trip min/avg/max/stddev = 0.887/0.953/1.299/0.057 ms