Changes in 1.6.0_20 (6u20)
The full internal version number for this update release is 1.6.0_20-b02 (where “b” means “build”). The external version number is 6u20.u20 contains Olson time zone data version 2010b.
A Java Network Launch Protocol (JNLP) file without a
codebase parameter, such as the following, will no longer work with the Java SE 6 update 20 release.
This means that developers must specify the
codebase parameter in a JNLP file. See the following example:
This release contains fixes for security vulnerabilities like :
Java : Mixed code warning for class.getResource(“directory/”) in 1.6.0_19
Javawebstart : Webstart Shows Wrong Exception when the same jnlp has a signed and a none signed jar
java_deploymentImprove Mixed Code Logging
Source : java.com