Hello Helmut,
1)
How to fix the permissions ?
Starting with 7.8.00.02 you can just run the command 'sdbverify -repair_permissions' to have access mask and owner/group reset to its installation default.
Unfortunately, there is no automated tool in your version to fix the permissions. You have to manually do that. Run the "sdbverify > sdbverify.txt" as a root user and check the sdbverify.txt output file to identify/check which permissions are modified/changed.
Refer to the WIKI below for the correct owner/group permissions and change them with chmod.
http://wiki.sdn.sap.com/wiki/display/MaxDB/UNIX+and+Linux+File+System+Permissions+for+SAP+MaxDB
2)
Download the MaxDB client software 7.7.07 >= Build 41 or higher from the SAP Marketplace
-> Software Downloads
-> 
Database and Database Patches (from other vendors)
-> SAP MaxDB
-> Database Patches"MAXDB 64-BIT
-> Choose the OS
-> MAXDB 7.7.07.46 Application Runtime Package
=>First stop the application server
=>Upgrade the SQLDBC runtime on all of your application servers.
=>Use Note 649814 to install or upgrade the SQLDBC runtime.
=>Restart the application server.
Regards,
Yashwanth