Sonar with Maven: Fail to connect to database: Cannot loa d JDBC driver class 'oracle.jdbc.OracleDriver'

Objective: Get Maven to publish sonar results to running Sonar server

Steps:

- Installed and ran Sonar, accessible from browser
- The back-end database is Oracle

Installed and configured Maven in settings.xml file to connect to the
Oracle db

Invoked: mvn clean install -DSkipTests=true
- Invoke: mvn sonar:sonar

But getting following mvn sonar:sonar Fail to connect to database: Cannot
load JDBC driver class 'oracle.jdbc.OracleDriver'

So I need somehow to put the ojdbc6.jar on Maven classpath. Tried placing
the ojdbc6.jar in /lib and lib/ext but did not help.

Am I missing something here? please help.

To fix this I modified *maven113home/bin/mvn*.bat at line 161 and added

%MAVEN_JAVA_EXE% %MAVEN_OPTS% -classpath path/to/ojdbc6.jar;...

*Which is nasty!*

Please suggest a better approach.