Error installing multiple 6.1 IS instances with SAP adapter

We are trying to implement 2 separate 6.1 IS environments on an HP-UX server, which include the SAP adapter (v4.6 SP5). We are not planning on using IS clustering at all, each instance will independent and have separate ports configured. The first instance was installed and configured with no issues at all. The SAP package loaded and the connections work fine. We’ve run into problems with the second instance. During start-up, then SAP package load is failing with the following error:
2005-01-04 15:11:37 EST [ISS.0028.0013E] Startup service exited with the following error: java.lang.reflect.InvocationTargetException: JCO.classInitialize(): Could not load middleware layer ‘’

The same SAP provided library files that are working in the first instance have been copied to the appropriate directory for the second instance. I’m wondering if the issue could be related to the environmental variables (JDKDIR and SHLIB_PATH) that the installation instruction have you set. Could there be a conflict with both instances trying to point to the same paths? If that’s the case, are there any alternatives?

Any ideas?

Thanks in advance,