Happy Bastille Day!
The IDV 2.7u1 release has been recompiled and refreshed to be backward 
compatible with systems still running Java SE 5 (aka Java 1.5).   You 
can download the release at:
http://www.unidata.ucar.edu/downloads/idv/2_7u1
This is being done to support Mac OS-X users since the default version 
of Java on that platform is Java 5 and there is no Java SE 6 for older 
PPC systems.  For Intel based Macs, Java 6 is available at:
http://support.apple.com/downloads/Java_for_Mac_OS_X_10_5_Update_4
Unfortunately, Apple does not plan to support Java 6 on the older systems.
This will be the last release to support Java SE 5.  Sun has announced 
that Java SE 5 support will end in October which means it will not 
provide updates (e.g. security fixes) after that date.  All the IDV 
installers have been including Java 6 since IDV 2.6 and Java 6 has been 
available on most platforms for over 2 1/2 years.  There are features of 
Java SE 6 that we would like to use to improve the capabilities of the 
IDV.  Also, the underlying netCDF-Java library will be using Java 6 for 
it's next release in September which will require us to move completely 
to Java 6.
We understand that this will impact some IDV users.  Unfortunately, 
security concerns, reliance on other packages and new features in Java 6 
require that we move to the current version of Java.
The IDV Developers.