Source server is getting hanged and connection to the server is getting disconnected at middle of processing.

Novell servers configuration as follows:
Source server:
Novell 6.5 sp5
TSAFS.NLM – V.6.51.04 DEC 6,2005
SMSUT.NLM – V.1.01.03 DEC 6, 2005
SMDR.NLM – V.6.54.04 NOV 16, 2005
Destination server:
Novell 6.5 sp7
TSAFS.NLM – V.5.50.11 NOV 5, 2004
SMSUT.NLM – V.1.00 NOV 5, 2004
SMDR.NLM – V.6.54.04 NOV 16, 2005

The following entries are from the log file created by NUWAgent.nlm during the Copy Files phase.

Destination Server: 'ASC_NW5', Source Server 'ASC_NW3'
Log File Name: '\\ASC_NW5\sys\system\migerror.log'
********************************************

'NWSMTS error: Received a record or subrecord trailer, but could not locate the trailer field.' (Source Server: ASC_NW5 Path: 'ACAD3:ACAD/22/D2210501.dwg' Error: 'fffdffef' Function: 'NWSMTSWriteDataSet'
Migerror.log message: 0xfffdffef NWSMTSWriteDataSet ASC_NW5 ASC_NW5 ACAD3:ACAD/22/D2210501.dwg)

'An unknown error has occurred.' (Source Server: ASC_NW5 Path: '' Error: 'fffeffcc' Function: 'NWSMTSCloseDataSet'
Migerror.log message: 0xfffeffcc NWSMTSCloseDataSet ASC_NW5 null)

'An unknown error has occurred.' (Source Server: ASC_NW5 Path: '' Error: 'fffeffcc' Function: 'NWSMTSScanNextDataSet'
Migerror.log message: 0xfffeffcc NWSMTSScanNextDataSet ASC_NW5 null)

**************************************
*** Begin SMS Error Log File ***
Source Server: ASC_NW5
Destination Server: ASC_NW5
*****************************************
*** Begin SMS Error Log File ***
Source Server: ASC_NW5
Destination Server: ASC_NW5

Invalid data (no data stream trailer) was found for ACAD3:ACAD/22/

D2210501.dwg.

Wed Mar 12 10:06:48 2008

Invalid data (no data stream trailer) was found for ACAD3:ACAD/22/

D2210501.dwg.

*** End SMS Error Log File ***

************************************************** ***************
End Server Log File
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- No one can log in to the source server. --- Error caused by a NetWare API error --- The connection to the server was lost. (Error code: 0X8819 Function Name: NWEnableFileServerLogin)

************************************************** ***************
Process stopped date: 03/12/08 time: 10:07:08
Elapsed time: Days: 0 Hours: 00 Minutes: 02 Seconds: 08
************************************************** ***************