Play dependencies for Play 1.3 and JDK 1.6

Hi,

a fews weeks ago, I could use play 1.3 with JDK 1.6, now when I execute, give me the next problem:

firstly, give me a warnings doing play dependencies:

play#secure;1.3.0: not found
play#crud;1.3.0: not found

The next problem is when try to generate .war.

Exception in thread “main” java.lang.UnsupportedClassVersionError: navigation/NavigationPlugin : Unsupported major.minor version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(ClassLoader.java:637)
at java.lang.ClassLoader.defineClass(ClassLoader.java:621)
at play.classloading.ApplicationClassloader.loadApplicationClass(ApplicationClassloader.java:166)
at play.classloading.ApplicationClassloader.loadClass(ApplicationClassloader.java:82)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
at play.plugins.PluginCollection.loadPlugins(PluginCollection.java:166)
at play.Play.init(Play.java:304)
at play.server.Server.main(Server.java:160)
~ Please fix compilation errors before packaging WAR

I know it is because execute with jdk 1.8 instead of doing jdk 1.6, and I set only 1.6 for the project.

When I do play dependencies and I generate .war with jdk version 1.8, the process finish corrrectly.

Any ideas? thanks!