A few insights:
1) Upgrading from r11.0 to r11.6 SP01, r11.0 already present
If we upgrade from r11.0 to r11.6 SP01 directly without uninstalling r11.6 SP01, the direct upgrade is not supported. Therefore, before you proceed to upgrade you have to uninstall the r11.0 product by issuing the "installp -u xcom62" command, and clean the txpi entries from the /etc/inetd.conf file and refresh the inetd service.
If you do not uninstall the product before proceeding to an upgrade, the symbolic links will not be correct.
2) Upgrading from r11.0 to r11.6 SP01, with r11.0 uninstalled
The r11.0 uninstaller does not clean up /etc/inetd.conf file.
In case of r11.6 SP00, installer force updates the txpi information in /etc/inetd.conf file, but in case of r11.6 SP01, we have made some changes in installer to update the /etc/inetd.conf file only when it does not find txpi details. This is done in order to retain the user’s customized locations.