error:INTERNAL.SYSTEM_NOT_CONFIGURED_AS_XMB

in http->xi->file

when i use http sender adapter with http client

i got the error message as follow:

<SAP:Error><SAP:Category>XIServer</SAP:Category>

<SAP:Code>INTERNAL.SYSTEM_NOT_CONFIGURED_AS_XMB</SAP:Code>

<SAP:Stack>System not configured as Integration Engine</SAP:Stack></SAP:Error>

any reply is appreciated

Thank you very much