can not autodetect the dialect

Hi,

I'm using oracle, I added the ojdbc14.jar in extensions/jdbc-driver/oracle,  sonar has created in my database tables like: users, schema_info, rules ...etc. On my project i'm not using maven2 but I added a pom.xml as shown in the guide of installation. when I tried to build my project, I got the following error:
[INFO] [sonar-core:prepare]
[ERROR] Cannot execute the command org.codehaus.sonar:sonar-core-maven-plugin:1.4.3:prepare
javax.persistence.PersistenceException: can not autodetect the dialect
    at org.sonar.commons.database.AbstractDatabaseConnector.getDialect(AbstractDatabaseConnector.java:169)
    at org.sonar.commons.database.DriverDatabaseConnector.getEntityManagerFactory(DriverDatabaseConnector.java:110)
    at org.sonar.commons.database.DriverDatabaseConnector.createEntityManager(DriverDatabaseConnector.java:138)
    at org.sonar.commons.database.BatchDatabaseManager.start(BatchDatabaseManager.java:45)
    at org.sonar.commons.DaoFacade.<init>(DaoFacade.java:39)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
    at org.picocontainer.injectors.AbstractInjector.newInstance(AbstractInjector.java:149)
    at org.picocontainer.injectors.ConstructorInjector.instantiate(ConstructorInjector.java:196)
    at org.picocontainer.injectors.ConstructorInjector$1.run(ConstructorInjector.java:169)
    at org.picocontainer.injectors.AbstractInjector$ThreadLocalCyclicDependencyGuard.observe(AbstractInjector.java:263)
    at org.picocontainer.injectors.ConstructorInjector.getComponentInstance(ConstructorInjector.java:192)
    at org.picocontainer.behaviors.AbstractBehavior.getComponentInstance(AbstractBehavior.java:66)
    at org.picocontainer.behaviors.Stored.getComponentInstance(Stored.java:85)
    at org.picocontainer.behaviors.AbstractBehavior.getComponentInstance(AbstractBehavior.java:62)
    at org.picocontainer.DefaultPicoContainer.startAdapters(DefaultPicoContainer.java:875)
    at org.picocontainer.DefaultPicoContainer.start(DefaultPicoContainer.java:641)
    at ch.hortis.sonar.mvn.CoreMojo.getContainer(CoreMojo.java:239)
    at ch.hortis.sonar.mvn.PrepareMojo.checkPluginsPresenceForProjectLanguage(PrepareMojo.java:147)
    at ch.hortis.sonar.mvn.PrepareMojo.doExecute(PrepareMojo.java:46)
    at ch.hortis.sonar.mvn.CoreMojo.execute(CoreMojo.java:130)
    at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:451)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:558)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeStandaloneGoal(DefaultLifecycleExecutor.java:512)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:482)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:330)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:291)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:142)
    at ch.hortis.sonar.mvn.SonarMavenEmbedder.execute(SonarMavenEmbedder.java:151)
    at ch.hortis.sonar.mvn.SonarMojo.executeMaven(SonarMojo.java:248)
    at ch.hortis.sonar.mvn.SonarMojo.executeGoals(SonarMojo.java:231)
    at ch.hortis.sonar.mvn.SonarMojo.execute(SonarMojo.java:116)
    at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:451)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:558)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeStandaloneGoal(DefaultLifecycleExecutor.java:512)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:482)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:330)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:227)
    at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:142)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:336)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:129)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:287)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
    at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
    at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:375)
Caused by: java.sql.SQLException: SQL driver not found org.apache.derby.jdbc.ClientDriver
    at org.sonar.commons.database.DriverDatabaseConnector.getConnection(DriverDatabaseConnector.java:87)
    at org.sonar.commons.database.AbstractDatabaseConnector.getDialect(AbstractDatabaseConnector.java:165)
    ... 51 more
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] Cannot execute the command org.codehaus.sonar:sonar-core-maven-plugin:1.4.3:prepare

Embedded error: can not autodetect the dialect
SQL driver not found org.apache.derby.jdbc.ClientDriver


Thanks for your help