jna load library

i'm having a problem on loading a dll with jna. While i can debug the code within eclipse, i get an Exception when i export and run it as a jar file:

java.lang.UnsatisfiedLinkError: unable to load library 'SiUSBXp'

Any ideas why it does not find my dll when i run it as a jar-file?

Thanks!!!!

public interface SiUSBXp extends StdCallLibrary {
    byte SI_GetNumDevices(IntByReference numdevices);
    byte SI_GetProductString( int deviceNum, byte[] productString, int options );
    byte SI_Open(IntByReference numdevices);
}

static SiUSBXp INSTANCE;

public static void main(String[] args) {
    System.setProperty("jna.library.path","SiUSBXp.dll");
    HashMap<String, StdCallFunctionMapper> optionMap = new HashMap<String, StdCallFunctionMapper>();
    StdCallFunctionMapper myMapper = new StdCallFunctionMapper();
    optionMap.put(Library.OPTION_FUNCTION_MAPPER, myMapper);
    INSTANCE = (SiUSBXp) Native.loadLibrary("SiUSBXp", SiUSBXp.class, optionMap);
}

------------------ EDIT ----------------------

The dll is located in the same folder as the jar is

------------------ E开发者_运维问答DIT 2 ---------------------

I've just tried to run it within windows xp and it works .. but it does not within windows 7 (64 bit)

------------------ EDIT 3 --------------------- I've solved the problem ... It was due to the java versions installed ... I removed them all, and then only installed the x86 version of java ... after that it worked perfectly

Put the DLL into the "Current Folder" or system variable PATH, or use -Djna.library.path=(path to the dll) as VM switch instead of hard-coding.