Hi,
Application server... "NARASIMHAECC"
Network address...... "192.168.100.1"
Are you able to download and apply OSS Notes on this system using SNOTE (is this system supported by SAP...)? There are quite a few OSS Notes with corrections for SAPLSTXK / LSTXKFRI relevant to SAP_BASIS 700 (more than I would risk trying to hack in via manual repairs), although I see none that fits the symptoms you describe exactly. To suggest something more about the exact Note numbers that might help one would need to know your SAP_BASIS service pack level as well.
cheers
Jānis