IBM Rational ClearCase mount.mvfs: Too many open files in system

There is a Linux host where ClearCase can’t mount any more VOBs

mount.mvfs: Too many open files in system

Reading this note on says the following:
The number of VOBs that can be mounted simultaneously under Linux is 1022, but this limit can be increased by configuring your MVFS. After you edit the mvfs_param.c file as described below for the kernel version of your system, rebuild and reinstall the MVFS or vnode module using the instructions contained in the README.txt file in the directory containing mvfs_params.c.

This is exactly the case on my system

root@linux:~ # df -h | grep vbs | wc -l