求救package之后的问题!!?

Exception in thread "main" java.lang.UnsatisfiedLinkError: no getMac in java.library.path何解？代码段:
package a;
.... static {System.loadLibrary("getMac");}
public native static String GetMac();
public static void main (String args[]){
getMac g = new getMac();
System.out.println(g.GetMac());
} getMac.dll跟程序在同一目录下!
如果没有用package;则可以正确运行的!
当package之后,我放到a目录下,运行:java a.getMac就出错了!
请高手指点!