I have multiple installation of java on my computer (jdk1.3,1.4,1.5) and JAVA_HOME is set to jdk1.3. I have checked this with "echo %JAVA_HOME%" in windows console.
But if I use $E(JAVA_HOME) I returned a path to another jdk installation.
I assume that we are talking about an installer built as a launcher distribution (otherwise, if you run the installer jar file with a command similar to "java -cp my_setup.jar run", check the PATH variable or use an explicit c:\jdk1.5\jre\bin\java or something like that command).
Most likely, the installer you built has its own java search process defined in the JVM Resolution section of the Additional Tools view. The JVM Search instructions in that section, or the contents of a "jvm" file (no extension) stored in a Bundled JVM points the installer to a JRE on your system. The installer launcher may be pointed to a specific java home with -is:javahome command line parameter, but the use of that parameter is limited to JRE hints (search path instructions) defined in a bundled jre or jre search instructions. Basically, if the installer launcher has no record of a JRE installed "z:\MyJunk\jre\bin\java", there is no way to force that installer launcher to use that jre.
A bundled JVM is a self-extracting zip file for a platform it's defined. It should uncompress the contents to a current directory if you run that file (on a system it was created for). Once a bundled jvm is uncompressed, look for "jvm" file in the current directory and inspect the contents for JRE search instructions.
You may search support.installshield.com for the jvm file format and a custom jre bundling instructions.
