Access control exception only on Linux/Debian not on Windows!?

Question

We have a rmi server application with a webstart rmi swing client that we have been running successfully on Windows. The client is downloaded and running without any problems on Windows platforms (W2003, Win2K, WinXP). The client webstart jar is signed and all permissions is set in the jnlp file.
As soon as we setup a server on linux/debian sarge we get these access control exceptions when the server tries to send events back to the client. It complains on
file permssions not being set on the server jar file and the strange thing is that the path separator is backslash on linux?
I've tried the following:
1) java.policy. Added All permssions to the server jar file and/or bin the folder.
2) Running without any security manager, i.e., System.setSecurityManager(null)
3) Explicitly setting the policy on the server. Policy.setPolicy(...)
4) Explicitly setting a policy on the client. URL policyUrl = Thread.currentThread().getContextClassLoader().getResource("server.policy");
5) Building the server and client on debian
I'm at my wits end... I've searched these forums and it seems that this is might be a common problem but I've not found a solution yet.
Our system works 100% on Windows without any problems, it's only on linux/debian that we get these access control problems.
2005-sep-19 09:39:19 se.xxx.xxx.admin.AdminManager change
ERROR: java.security.AccessControlException: access denied (java.io.FilePermission \\usr\local\XXX\bin\server.jar read)
java.security.AccessControlContext.checkPermission(Unknown Source)
java.security.AccessController.checkPermission(Unknown Source)
java.lang.SecurityManager.checkPermission(Unknown Source)
java.lang.SecurityManager.checkRead(Unknown Source)
java.io.File.exists(Unknown Source)
sun.net.www.protocol.file.Handler.openConnection(Unknown Source)
sun.net.www.protocol.file.Handler.openConnection(Unknown Source)
java.net.URL.openConnection(Unknown Source)
sun.rmi.server.LoaderHandler.addPermissionsForURLs(Unknown Source)
sun.rmi.server.LoaderHandler.access$300(Unknown Source)
sun.rmi.server.LoaderHandler$Loader.<init>(Unknown Source)
sun.rmi.server.LoaderHandler$Loader.<init>(Unknown Source)
sun.rmi.server.LoaderHandler$1.run(Unknown Source)
java.security.AccessController.doPrivileged(Native Method)
sun.rmi.server.LoaderHandler.lookupLoader(Unknown Source)
sun.rmi.server.LoaderHandler.loadClass(Unknown Source)
sun.rmi.server.LoaderHandler.loadClass(Unknown Source)
java.rmi.server.RMIClassLoader$2.loadClass(Unknown Source)
java.rmi.server.RMIClassLoader.loadClass(Unknown Source)
sun.rmi.server.MarshalInputStream.resolveClass(Unknown Source)
java.io.ObjectInputStream.readNonProxyDesc(Unknown Source)
java.io.ObjectInputStream.readClassDesc(Unknown Source)
java.io.ObjectInputStream.readOrdinaryObject(Unknown Source)
java.io.ObjectInputStream.readObject0(Unknown Source)
java.io.ObjectInputStream.readObject(Unknown Source)
sun.rmi.server.UnicastRef.unmarshalValue(Unknown Source)
sun.rmi.server.UnicastServerRef.dispatch(Unknown Source)
sun.rmi.transport.Transport$1.run(Unknown Source)
java.security.AccessController.doPrivileged(Native Method)
sun.rmi.transport.Transport.serviceCall(Unknown Source)
sun.rmi.transport.tcp.TCPTransport.handleMessages(Unknown Source)
sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(Unknown Source)
java.lang.Thread.run(Unknown Source)
sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(Unknown Source)
sun.rmi.transport.StreamRemoteCall.executeCall(Unknown Source)
sun.rmi.server.UnicastRef.invoke(Unknown Source)
se.xxx.xxx.client.XXXApplication_Stub.notify(Unknown Source)
)

Answer 1

I have two suggestions. The first is that you didn't indicate the permissions of the file and the directories above it along with the user you're running the program as. In Unix it is easier to get an access issue as you're probably not running as root. In a traditional Windows environment everything runs with admin permission allowing access to anything. While the error comes from the security manager it has nothing to do with traditional J2SE security - it may be an O/S level thing.
But the second suggestion touches on the other question you have - why is this showing up as backslashes? Is there perhaps an issue with the JNLP file? Is there any code that should be using System.getProperty( "file.separator") and is instead just using the backslash?