Printers get Disconnecter after about an hour

Hi,

I have a small DOS program that is running on Win98 clients connected to a
Win2000 server. Furthermore, I am using printers at another location,
connecting with ADSL. In the Win98 clients I use a login script " NET USE
LPTx: \\<IP Address>\PrinterName " to map to the printer on the remote
computer.

The version of the NET (Net Ver) is MS-Client 4.0
The Win98 version is 4.10.2222

The problem is that after about an hour the printer on the remote computer
gets disconnected (I see that when I issue the NET USE statement) and the
DOS program comes up with an error that it can not print to that port. The
only workaround I have found is to Delete that share (with Net Use /D Lptx)
and connect to it again. This must be a setting somewhere ?!? I know that in
XP there is a /Persistent swithc with the Net Use Command and even NET
CONFIG SERVER /AUTODISCONNECT:-1 you can do but neihter of this is present
in Win98.

Do you hav any idea how I can resolve this ?

Regards
Stefan