Customer received exception release
jre-6u2-erdist-bin-b07-windows-i586-p-30_jul_2007.bin
which identifies itself as

F:\> java -version
java version "1.6.0_02-erdist"
Java(TM) SE Runtime Environment (build 1.6.0_02-erdist-b07)
Java HotSpot(TM) Client VM (build 1.6.0_02-erdist-b07, mixed mode, sharing)

When starting Web Start applications with Java Web Start 1.4.2
running on JRE 1.6.0_02-erdist, runtime of Java 6 ER is not recognized.
This leads to the following two alternatives (monitor by Java console):
- the most recent of all installed JREs besides JRE 6 ER is used
- JRE 6 is auto-downloaded, when the use of JRE 6 ER is enforced
  by disabling all other installed JRE's, except the JRE 6 ER in
  javaws -> File -> Preferences -> Java -> Java Runtime Versions enabled
Same thing happens with the following release:

F:\>java -version
java version "1.6.0_06-ea"
Java(TM) SE Runtime Environment (build 1.6.0_06-ea-b01)
Java HotSpot(TM) Client VM (build 10.0-b22, mixed mode, sharing)

F:\>
Same thing happens with the following release:

F:\>c:\jre6\bin\java -version
java version "1.6.0_10-beta"
Java(TM) SE Runtime Environment (build 1.6.0_10-beta-b13)
Java HotSpot(TM) Client VM (build 11.0-b11, mixed mode, sharing)

F:\>
Same thing happens with the following release:

C:> c:\jdk1.6.0_10\bin\java -version
 java version "1.6.0_10-rc"
 Java(TM) SE Runtime Environment (build 1.6.0_10-rc-b28)
 Java HotSpot(TM) Client VM (build 11.0-b15, mixed mode, sharing)

 which is publicly available.