Cognos 10.2.1 for Linux AMD64 is not starting

[gabbagabba]

I am running IBM Cognos BI Server on Red Hat Enterprise Linux 6.5 64 bit, using for content store a databases residing on a DB2 Express-C server located in the same computer. I already copied the DB2 client JAR files and when testing the database connection works just fine, but when I try to start Cognos from Cognos Configuration I get a lot of messages like this one and Cognos fails to start:

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18:08:18, CM-SYS-3089 The Content Manager configuration parameter "CMEnableAuthenticateMethod" is not valid for this database type.
18:08:18, CM-SYS-3089 The Content Manager configuration parameter "CMDbDriverOracle" is not valid for this database type.
18:08:18, CM-SYS-3089 The Content Manager configuration parameter "CMEnableSystemStateReq" is not valid for this database type.

I already looked everywhere around the internet and nobody seems to have the answer. What's happening?