After upgrading the Netextender client to the latest version 10.2.319 IPV6 DNS entries are added in Netextender resulting in failure of DNS name resolution. There are no issues with connectivity and access to internal resources.
This Issue has been reported and a fix is currently under development. In the mean time, It is recommended to use 10.2.315.
NOTE: This Issue is specifically reported against NetExtender version 10.2.319 while connecting to firewalls and not against SMA products.