As we know that Weblogic and OEPE installation are pre-requisites for OSB11g installation. Oracle had started shipping Weblogic bundled with Coherence and OEPE. Using this Weblogics installer is the best way to get compatible OEPE for a particular release. However, these are not available for 64-bit machines and need to do manual installation JDK, Weblogic using generic Installer, compatible OEPE version along with your required version of OSB 11g.
So you need to better understand compatible versions of OEPE for a particular OSB 11g release. The following shows the compatibility matrix:
OSB | Weblogic Server | OEPE |
11.1.1.6.0 11.1.1.7.0 |
10.3.6 | 11.1.1.8.0 |
11.1.1.5.0 | 10.3.5 | 11.1.1.7.2 |
11.1.1.4.0 | 10.3.4 | 11.1.1.6.1 |
11.1.1.3.0 | 10.3.3 | 11.1.1.5 |
These versions of Oracle Enterprise Pack for Eclipse are available here.