Conflict between gatling and cassandra

Gatling (Open-Source)
1

I´m start using gatling with this maven dependency

io.gatling.highcharts gatling-charts-highcharts 2.2.5 test

But I´m having then problems with my Cassandra component that use this dependency

com.datastax.cassandra cassandra-driver-core ${cassandra.driver.core.version} slf4j-api org.slf4j

When I see the logs I can see this exception

INFO 2017-04-25T14:31:43,119 [] [com.datastax.driver.core.GuavaCompatibility] Detected Guava < 19 in the classpath, using legacy compatibility layer
INFO 2017-04-25T14:31:44,000 [] [com.datastax.driver.core.Native] Could not load JNR C Library, native system calls through this library will not be available (set this logger level to DEBUG to see the full stack trace).
INFO 2017-04-25T14:31:44,000 [] [com.datastax.driver.core.ClockFactory] Using java.lang.System clock to generate timestamps.
WARN 2017-04-25T14:31:44,789 [] [com.datastax.driver.core.NettyUtil] Found Netty’s native epoll transport, but not running on linux-based operating system. Using NIO instead.
WARN 2017-04-25T14:31:46,457 [] [io.netty.util.concurrent.DefaultPromise] An exception was thrown by com.datastax.driver.core.Connection$1.operationComplete()
java.lang.NullPointerException
at io.netty.channel.group.DefaultChannelGroup.add(DefaultChannelGroup.java:146) ~[netty-transport-4.1.5.Final.jar:4.1.5.Final]
at io.netty.channel.group.DefaultChannelGroup.add(DefaultChannelGroup.java:42) ~[netty-transport-4.1.5.Final.jar:4.1.5.Final]
at com.datastax.driver.core.Connection$1.operationComplete(Connection.java:161) ~[cassandra-driver-core-3.2.0.jar:?]
at com.datastax.driver.core.Connection$1.operationComplete(Connection.java:148) ~[cassandra-driver-core-3.2.0.jar:?]
at io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:514) [netty-common-4.1.5.Final.jar:4.1.5.Final]
at io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:488) [netty-common-4.1.5.Final.jar:4.1.5.Final]
at io.netty.util.concurrent.DefaultPromise.access$000(DefaultPromise.java:34) [netty-common-4.1.5.Final.jar:4.1.5.Final]
at io.netty.util.concurrent.DefaultPromise$1.run(DefaultPromise.java:438) [netty-common-4.1.5.Final.jar:4.1.5.Final]
at io.netty.util.concurrent.GlobalEventExecutor$TaskRunner.run(GlobalEventExecutor.java:233) [netty-common-4.1.5.Final.jar:4.1.5.Final]
at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:144) [netty-common-4.1.5.Final.jar:4.1.5.Final]

Any idea how to fix this conflict?

Regards.