How to unload a dll in java

After loading the native library through System.loadLibrary , we were unable to unload the dll , i have tried entering the Registry Values of current windows version creating key alwaysunloaddll to 1 and also through c/c++ Wrapper Classes Using JNI but nothing worked out As the Dll is loaded in to the memory ,So Please Let Me know if there is any other way to Unload the Library in java? it is an Urgent Requirement so any comments and suggestions are appreciated ,Thanks in advance

Thanks a lot,i really appreciate of taking time to answer my questions ,but im afraid that i have already used System.gc but i was unable to unload the library , But i think custom class loaders is only ray of hope so ,can anybody send me a code to unload the native library ,coz im a laymen to the concept of class loaders, or please do let me know if there is any alternate way of unloading the library Afterall there is a solution for every problem Right!Thanks once again ............

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