Uploading to linux-Apache1.3.20 from win2k is working too ...... slow.

I have Mandrake 8.1 installed on my network,with Apache from the distribution cd-s


I have some scripts that uploads files to the server,using php.
All the computers from the network are working fine except 2 comps that have win2k professional installed on.

When I try to upload files from win2k to the server, it takes too much time(3 minutes for a 30k file !!!), but downloads are working normal.
From the log files I saw that there is not a problem with php, but is a problem with the connection, the packet exchenge between those computers is too slow.

So my question is why this is working on win95 or win98 clients but not on win2k. Is there something with win2k that tries to optimize the connection but it's dooing exactly the oposite thing?

If there is someoane that can give me a hint, pls help me.
I'm so confused!

And another two things:
- I have installed SP2 on win2k machines(so this is not the sollution)
- I have tested it from netscape4.7 and from IE6 and IE5.5
- PLS HELP!

Look if there is an error runnin scripts. Or install tcpdump, try to connect from Windows and read the packets (but it's time-consuming solution)