Java web start JRE auto-download does not work in vista. The JNLP jre installer can be download and launched, but when we do a Runtime.exec on the jre installer itself, the create process failed: (even a standalone java application that do a Runtime.exec on the installer fail too)

execute !C:\jre59234.dat /s /v"/qn WEBSTARTICON=1 INSTALLDIR=\"C:\Program Files\
Java\j2re1.4.2_07\\""!

java.io.IOException: CreateProcess: C:\jre59234.dat /s /v"/qn WEBSTARTICON=1 INS
TALLDIR=\"C:\Program Files\Java\j2re1.4.2_07\\"" error=740
        at java.lang.ProcessImpl.create(Native Method)
        at java.lang.ProcessImpl.<init>(Unknown Source)
        at java.lang.ProcessImpl.start(Unknown Source)
        at java.lang.ProcessBuilder.start(Unknown Source)
        at java.lang.Runtime.exec(Unknown Source)
        at java.lang.Runtime.exec(Unknown Source)
        at java.lang.Runtime.exec(Unknown Source)
        at test.execute(test.java:12)
        at test.main(test.java:6)