Outbound IDoc can not be sent

I'm having trouble sending out an outbound IDoc with the following partner information from ECC:

         <SNDPOR>ECC_DEV</SNDPOR>

         <SNDPRT>KU</SNDPRT>

         <SNDPRN>1002</SNDPRN>

         <RCVPOR>PI_DEV</RCVPOR>

         <RCVPRT>KU</RCVPRT>

         <RCVPRN>1002</RCVPRN>

When I change the settings to the following the IDoc is received in PI (7.31 AEX) succesfully:

         <SNDPOR>ECC_DEV</SNDPOR>

         <SNDPRT>LS</SNDPRT>

         <SNDPRN>ECC</SNDPRN>

         <RCVPOR>PI_DEV</RCVPOR>

         <RCVPRT>KU</RCVPRT>

         <RCVPRN>1002</RCVPRN>

The error message received in PI is "No Party configured for key = ALE#KU". I already tried the solutions mentioned in this document: http://www.sdn.sap.com/irj/scn/go/portal/prtroot/docs/library/uuid/cdded790-0201-0010-6db8-beb9bb2b2660?QuickLink=index&overridelayout=true&5003637721826