This and similar issues have been discussed earlier I several different threads but no working solution has yet been posted on the forum as far as I am aware. Only workarounds that are unacceptable in our environment have been posted.
Another similar old thread: "Windows 7 - NcFsd under Mapped Drive"

Problem description:
In our university we have sleep mode enabled on our Windows 7 client workstations because of the energy savings. We also run Windows XP clients in the same environment (but they do not enter sleep/standby automatically). The sleep timeout on the Windows 7 clients is set to 30 minutes, sometimes when users come back from their lunch breaks or come back to work the next day after only locking their computers (no logging off) the first login attempt fails with this error: The network password cannot be validated at this time because the connection to the Novell network was lost. The connection to network drives that have been mapped in the login-script including the home-folder (H :) is also lost and sometimes but not always the drives are listed as disconnected under Computer in Windows Explorer. The network drives are sometimes automatically reconnected after a few seconds but other times it takes several minutes until the drives are accessible, which is a big deal. The error when logging in is now solved in Novell Client 2 SP2 (IR5) where only the windows-only logon is show when computers are woken from sleep, but I still have no acceptable solution to the disconnected drives.

Windows 7 Enterprise 64-bit with Novell Client 2 SP2 (IR5)
ZENworks 11 SP 1, exactly the same problem is occurring on clients without ZENworks
OES 2 SP2 file server for backwards compatibility with XP clients
Dynamic IP and DNS (both work instantly when computers are woken from sleep)

Here is all the relevant information I have gathered regarding this issue at this point:
Disabling sleep: completely solves the problem but this is the last solution because of the energy savings that are lost and this really should be expected to work in school/business-environments in the year 2012. I also know this works better in full Microsoft environments.
It has been suggested to turn of Power Management for the clients NICs but this disables sending a Wake on LAN from ZCM to computers that are in sleep, which is unacceptable since we use it to remotely managed devices across several different sites.
Enabling the Novell System tray icon allow users to do a manual Novell Login which maps the network drives again and make them accessible, the same can be achieved by logging out and then logging in again. This is a workaround and not a solution.
While the network drives are disconnected the file server can be pinged and a DNS-lookup returns the correct IP address.
While network drivers are disconnected it I possible to see the contents of folders that have been left open (probably some windows cache). The file-server to which the network mappings have been made is visible under Network in Windows Explorer but trying to access folders within the server deeper than one level fails. Also refreshing the objects visible under Network in Windows Explorer visually removes the file-server and adds it again but the network-drives and folders are still not accessible. Refreshing the network-mappings under Computer in Windows Explorer also has no effect.
A Wireshark capture shows the NCP-protocol sending the following message from the client to the file-server when trying to browse folders: Completion Code: 255 (0x89ff), No matching files or directories were found. After what seems to be a random time or interval the drives start working again and that is right after a number of these messages are sent from the client to the file-server (again NCP-protocol): Function: 87 (0x57), Clear Physical Record to which the file-server the replies OK. It seems to me like there is some kind of timeout that might be adjustable to correct this or maybe the is something that can be done manually on the client to refresh the drives, a solution where the user manually clicks a script or a script is automatically run when the user unlocks the computer would be an accepted workaround.

Are there any suggestions as to what might be causing this and how to solve it or any know workarounds that I should try before opening a Support Request with Novell?