2 SAP Adapter Questions

Do I have to define an External RFC Server if I only want to call into SAP from IntegrationServer?
From the documentation, it implies I need it for calls FROM SAP to IntegrationServer.

Trying to define an SAP server connection, I can connect when I set the External RFC Server to NO.

If I set it to YES (and supplying the correct RFC params like program ID and Gateway host), I get the following error message:

2002-04-11 10:18:09 EDT com.sap.mw.jco.JCO$Exception: (108) JCO_ERROR_INTERNAL: Wrong repository version = 0 encountered

I tried changing the Default XRFC Version to both 1.0 and 0.9 but neither works.
SAP version is 3.1H

Any ideas or suggestions are greatly appreciated!!