JavaCard OS

Hi there! I went to compile my JavaCard applet and got the following message:

warning: This package requires int support.
error: export file util.exp of package java.util not found.
conversion completed with 1 errors and 1 warnings.

How do I resolve the warning and the error? Any clues would be appreciated!

warning: This package requires int support.

This is only a warning. Check your code, the variable(s) with type "int" you used. Normally, javacard uses type "short". If you have to use type "int", please make sure that your card support it. (The JCVM must implement the class javacardx.framework.util.intx.JCint)

error: export file util.exp of package java.util not found.

JavaCard API didn't support the package java.util. What's the api you used in package java.util? Tell us first.

Waiting your message.

I have the same warning, that is
So what is the solution now, I do still not fix that. I was checked again I am sure that I do not use the integer variable.