First, JDK 1.7 is not certified with Forms 11gR2. Only JDK 1.6 familly is certified and supported.
It seems to be an environment/installation issue as this installation works fine.
- Are you installing as Admin user and running Builder as the with the same OS user?
- Let me know the WLS 10.3.6 complete zip file name you installed and the command you used to install it. Also the 11.1.2 file names for review
As a workaround:
You can open rwrun.jar in Jdeveloper and check the classpath in the manifest.
I remembered i had an issue on this(184.108.40.206 version) when rwrun.jar called a jar file javax.jsp_220.127.116.11_2-1.jar that did not exist in the installaton(There was a newer version like javax.jsp_18.104.22.168_2-1.jar in the installation).
Normally should not be happening in 11gR2, but give it a try.
If someone's answer is helpful or correct please mark it accordingly.
what you are facing is the following known issue.
Problems Running JSP Reports in 11.1.2 and WLS 10.3.6 - Blank/Empty Page or REP-0177 and java.lang.NoClassDefFoundError: javax/servlet/jsp/tagext/TagLibraryInfo (Doc ID 1493783.1)