If a Windows NT Lotus Notes client fails to connect or continually drops connections to a database: the client time-out value may need to be increased to maintain a dormant connection. This tends to happen to Lotus Notes clients when there is no activity on the network connection. This is also true for net shares. The default is 10 minutes (600secs). Its not a big issue except for Notes clients but you can reduce some network traffic (awakening dormant connections), if you lengthen the KeepConn period.

Hive: HKEY_LOCAL_MACHINE
Key: SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters
Name: KeepConn
Type: REG_DWORD
Value: 2000 decimal