On Tue, Aug 07, 2007 at 12:18:11PM +0200, Zafer Aydogan wrote:
> Does anybody know what could be the reason ?

Yes, it's a problem with the default configuration of Mac OS X's TCP.
Please create a file "/etc/sysctl.conf" with the following content
on all the Mac OS X clients:

net.inet.tcp.delayed_ack=0

Run "sysctl -w net.inet.tcp.delayed_ack=0" manually afterwards to
change the setting without rebooting.

	Kind regards

-- 
Matthias Scheler                                  http://zhadum.org.uk/