A DESCRIPTION OF THE REQUEST :
If the Verisign timestamping certificate at:-

https://knowledge.verisign.com/resources/sites/VERISIGN/content/live/SOLUTION/9000/SO9699/en_US/TimestampCA.cer

was added to cacerts in the JRE then timestamping of applets would be possible using the jarsigner option -tsa https://timestamp.geotrust.com/tsa which is also from Verisign (they own Geotrust).

This certificate is already included with Firefox so why not in the JRE too?

JUSTIFICATION :
Timestamping proves the date of the jar signing and can allow jar expiry to be extended beyond the signing cert expiry date. In one test with a one year signing cert the jar expiry was extended to around 9 years. This means the users do not get bothered with untrusted security alerts after only one year.

In a nutshell - less hassle for users.