BUG? Ruby 1.8.4 readpartial oddities

Hello Core,

We are using ruby  cvs. Both windows and linux

ruby 1.8.4 (2006-03-23)

On linux, server:
require 'socket'

puts "Ruby version is #{RUBY_VERSION} on #{`uname -a`.strip}"
socket = UDPSocket.new
socket.bind("0.0.0.0", 666)
puts "Listening to UDP socket port 666"

while(true) do
        puts "Read: #{socket.readpartial(10)}"
end


On windows 2000:

Sending traffic to the server with netcat like this:
nc -u <server_ip> 666
123456789
123456789
123456789
1234567890

Produces the following output:
Ruby version is 1.8.4 on Microsoft Windows [Version 5.2.3790]
Listening to UDP socket port 666
Read: 123456789
Read: 123456789
Read: 123456789
ruby_184_windows_readpartial.rb:9:in `readpartial': Invalid argument
(Errno::EINVAL)
        from ruby_184_windows_readpartial.rb:9

 This shouldn't fail with EINVAL.

On linux:

Sending traffic to the server with netcat like this:
nc -u <server_ip> 666
123456789
123456789
123456789
1234567890
12345678901
123456789012

Produces the following output:
Ruby version is 1.8.4 on Linux <server> 2.4.29+smp #1 SMP Fri Apr 15
12:06:52 UTC 2005 i686 GNU/Linux
Listening to UDP socket port 666
Read: 123456789
Read: 123456789
Read: 123456789
Read: 1234567890
Read: 1234567890
Read: 1234567890


Note that this behaviour is odd as well, it loses the remaining bytes from
the packets..
I would have expected to receive the 1 and the 12 from the packets in the
next readpartial calls,
 but maybe thats an UDP socket *feature* and not a bug. Ok, honestly, the
data should not go missing.
Most importantly though, the readpartial never raises Invalid argument like
it does on windows.