samba - May 2007 - samba and winxp problem with FAT32 shares

Hi,

I have a FC5 linux PC in the LAN where samba is configured. I connected a
2GB usb flash drive to it and created a share to access it through lan. The
flash drive is a FAT32 one. I have mounted it like this "mount -t vfat -o
umask=000 /dev/sda1 /mnt/usbdisk".

I am able to read/write small files but when I tried to copy a movie of some
467MB file into the share I got an error "The specified network name no
longer exists" after a some time of initiating copy. Through ethereal I was
able to know that windows is not giving response for some time and trying to
reconnect three or four times on different ports. I want to know if this is
windows problem or a samba problem. My samba logs when the error occured is
this:

[2007/04/29 11:45:03, 0] smbd/oplock.c:oplock_break(758)
   oplock_break: receive_smb error (Success)
   oplock_break failed for file mov001.dat (dev = 812, inode
= 1646447, file_id = 1118).
[2002/04/29 11:45:03, 0] smbd/oplock.c:oplock_break(843)
   oplock_break: client failure in break - shutting down this smbd.

-- Mohan