Workflow 6.1.5 with Integration server6.5

Hi,

I have Integartion server 6.5 installed on my PC. Now i have workflow version 6.1.5 installed. when i try connecting to through workflow server i get errors as

Invalid configure.jar
Invalid clientmgr.jar
Invalid designer.jar

Please let me know how to get rid of such error.
Also I want to know whether both are compatible or not.
Your Help in this problem is desired and appreciable.

Thanks
Amit