I am having troubles getting Selenium Grid to start Selenium Server on slaves. When I try manually starting Selenium server on the slaves it works great.

I am getting this error all the time:

[12/09/14 17:15:48] [SSH] Starting slave process: cd "C:\cygwin64\home\$USER\selenium-server" && java -jar slave.jar
<===[JENKINS REMOTING CAPACITY]===>channel started
Slave.jar version: 2.48
This is a Windows slave
Starting Selenium nodes on Thor IE11 - Win8.1
$ "C:\Program Files\Java\jre1.8.0_25\bin\java" -Dwebdriver.ie.driver=C:\cygwin64\home\$USER\selenium-server\IEDriverServer.exe -cp C:\cygwin64\home\$USER\selenium-server\slave.jar hudson.remoting.Launcher -cp C:\cygwin64\home\$USER\selenium-server\selenium-server-standalone-2.41.0.jar -connectTo localhost:57416
ERROR: Unexpected error in launching a slave. This is probably a bug in Jenkins.
java.lang.NullPointerException
at hudson.plugins.selenium.callables.SeleniumCallable.invoke(SeleniumCallable.java:98)
at hudson.plugins.selenium.callables.SeleniumCallable.invoke(SeleniumCallable.java:24)
at hudson.FilePath$FileCallableWrapper.call(FilePath.java:2677)
at hudson.remoting.UserRequest.perform(UserRequest.java:121)
at hudson.remoting.UserRequest.perform(UserRequest.java:49)
at hudson.remoting.Request$2.run(Request.java:324)
at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:68)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
at ......remote call to Thor IE11 - Win8.1(Native Method)
at hudson.remoting.Channel.attachCallSiteStackTrace(Channel.java:1356)
at hudson.remoting.UserResponse.retrieve(UserRequest.java:221)
at hudson.remoting.Channel.call(Channel.java:752)
at hudson.FilePath.act(FilePath.java:970)
at hudson.FilePath.act(FilePath.java:959)
at hudson.plugins.selenium.process.SeleniumJarRunner.start(SeleniumJarRunner.java:46)
at hudson.plugins.selenium.configuration.global.SeleniumGlobalConfiguration.start(SeleniumGlobalConfiguration.java:55)
at hudson.plugins.selenium.PluginImpl.startSeleniumNode(PluginImpl.java:444)
at hudson.plugins.selenium.ComputerListenerImpl.onOnline(ComputerListenerImpl.java:26)
at hudson.slaves.SlaveComputer.setChannel(SlaveComputer.java:531)
at hudson.slaves.SlaveComputer.setChannel(SlaveComputer.java:366)
at hudson.plugins.sshslaves.SSHLauncher.startSlave(SSHLauncher.java:945)
at hudson.plugins.sshslaves.SSHLauncher.access$400(SSHLauncher.java:133)
at hudson.plugins.sshslaves.SSHLauncher$2.call(SSHLauncher.java:711)
at hudson.plugins.sshslaves.SSHLauncher$2.call(SSHLauncher.java:696)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
[12/09/14 17:15:59] Launch failed - cleaning up connection
[12/09/14 17:15:59] [SSH] Connection closed.
ERROR: Connection terminated
java.io.IOException: Unexpected termination of the channel
at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:50)
Caused by: java.io.EOFException
at java.io.ObjectInputStream$PeekInputStream.readFully(ObjectInputStream.java:2325)
at java.io.ObjectInputStream$BlockDataInputStream.readShort(ObjectInputStream.java:2794)
at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:801)
at java.io.ObjectInputStream.<init>(ObjectInputStream.java:299)
at hudson.remoting.ObjectInputStreamEx.<init>(ObjectInputStreamEx.java:40)
at hudson.remoting.AbstractSynchronousByteArrayCommandTransport.read(AbstractSynchronousByteArrayCommandTransport.java:34)
at hudson.remoting.SynchronousCommandTransport$ReaderThread.run(SynchronousCommandTransport.java:48)