Hello Christian,
PATH has to be set for Windows, LD_LIBRARY_PATH for Unix/Linux environments.
Let me point you to our (very good) selection of MaxDB FAQ notes, in this case SAP note 822271:
"14. The SAP recommendations for LIBRARYPATH are confusing and sometimes appear contradictory. How can I set these environment variables correctly?
MaxDB kernel version lower than 7.8
The environment variable LD_LIBRARY_PATH must contain INDEPPROGRAM/lib in Unix.
MaxDB Kernel Version 7.8 and higher
The environment variable LD_LIBRARY_PATH must contain ClientProgPath/lib on Unix."
Regards,
Thorsten