I just tried that last week.
With SUM 8.1.
You put the SAR file in a directory by itself.
This is the compliment to a stack - you put the stack of SAR, jar, SCA, xml in a unique directory.
/usr/sap/trans/EPS/in is unsuitable because it might have reminants from prior maintenance.
You CAN use JSPM to upgrade the SAP JVM. /usr/sap/trans/EPS/in is the correct location for that tool.
Are you using Wily agents?
SUM 8.1 crapped out generating the connector.jar, so i'm now running without wily.
Use JSPM or an earlier SUM.
Ken