Calling a RFC with XI 2.0

Hi.

I'm trying to call the RFC_FUNCTION_SEARCH using XI 2.0 but I just get the following error:

<Trace level="1" type="System_Error">Exit XMB because of system error!</Trace>

<Trace level="1" type="System_Error">System-Error: RFC_ADAPTER.SYSTEM_FAILURE_INTERNAL</Trace>

<Trace level="1" type="System_Error">Integration Engine runtime error (incomplete connect information missing field: null) </Trace>

I don't know what could be the missing field. I can import the RFC with no problem in the Directory.

Thank you,

Fabiano.