使用Java引导类装入器装入的库的替代方法

I need use the both jars local_policy.jar and US_export_policy.jar with unlimited key size strength. The JRE comes bundled with versions of the jars, with limited key size strength. But I can't replace the original jars in the $JAVA_HOME/lib/security (insufficient rights), so i need them to override (at runtime?) somehow.I need use the both jars local_policy.jar and U