Changes we have made in 7u51 and JDK8 and 8u5 require small modification to the JNLP Specification for 8u20:
1.) specification says we must ignore unlisted manifest entries.
    We need to change it to say JNLP Client may ignore unspecified manifest attributes.
    We need to add line to say it is permissible for JNLP Client to require manifest attributes such as "Permissions" in main jar or in all jars.
2.) specification lists SocketPermission for download host as required permission for untrusted environments. Since we now create URLPermission instead if running JDK8 or later, we should remove this from the table of required permissions.
3.) remove platform attribute to information block.
4.) make vendor attribute no longer mandatory in an information element. (which makes information element no longer mandatory)

see details at wiki: http://wiki.se.oracle.com/display/JPGC/JNLP+Spec+Changes