How to get JNA working with JavaME

I created a wrapper of a C library with JNA and all is working. Now I'm trying to use the wrapper in a JavaMe project, but with no success.
I.m using javaME SDK 8.2 and JNA 4.2.1.
In NetBeans 8,1 I added JNA-4.2.1.jar and my wrapper to a JavaME project,just as I did with a Java project. I can build it, but when I try to run the project on the emulator I get the following error (the line where I have the error is where I try to access some JNA code):

`Starting emulator in execution mode
Trying starting IMlet...
TRACE: , startApp threw an Exception
java.lang.UnsupportedClassVersionError

• java/lang/Class..unknown.(), bci=0
• java/lang/Class.initialize(), bci=110
• JavaMEApplication2.startApp(JavaMEApplication2.java:47)
• .unknown...unknown.(), bci=1
• .unknown...unknown.(), bci=5
• .unknown...unknown.(), bci=236
• .unknown...unknown.(), bci=38
• .unknown...unknown.(), bci=5
• .unknown...unknown.(), bci=127
• com/sun/midp/main/AppIsolateMIDletSuiteLoader.main(), bci=26
  java.lang.UnsupportedClassVersionError
• java/lang/Class..unknown.(), bci=0
• java/lang/Class.initialize(), bci=110
• JavaMEApplication2.startApp(JavaMEApplication2.java:47)
• .unknown...unknown.(), bci=1
• .unknown...unknown.(), bci=5
• .unknown...unknown.(), bci=236
• .unknown...unknown.(), bci=38
• .unknown...unknown.(), bci=5
• .unknown...unknown.(), bci=127
• com/sun/midp/main/AppIsolateMIDletSuiteLoader.main(), bci=26
  BUILD SUCCESSFUL (total time: 39 seconds)`

Would anyone have an idea about what's happening ?
Thanks

Start at JavaMEApplication2.java:47 and reproduce the emulator failure using JavaME SDK 8.2, JNA 4.2.1, and the native wrapper. Compare the JavaME runtime requirements with the included JNA JAR and wrapper; done means identifying whether this combination is supported and documenting a confirmed configuration or compatibility limitation.