Windows NT uses the TickCount in the NetWare routing packet to calculate a round trip time.
A tick is 1/16 of a second. If a tick count of 2 is announced, CSNW will retransmit a missing NCP packet in 110 ms.
To fix this problem, install Service Pack 5.
Use Regedt to navigate to:
On the Edit menu, Add Value name TickCountModifier as a type REG_DWORD.
Set the data value to a number in the range of 1 - 255. This will increase the tick count by this number,
increasing the time it takes for Windows NT to retransmit a packet.