SPOOL_INTERNAL_ERROR in PI 7.1

Hi Experts,

The PI system generating lot of SPOOL_INTERNAL_ERROR(ST22: ABAP runtime error) with terminating RSXMB_RESTART_MESSAGES program .

Error Description:

Runtime Error: SPOOL_INTERNAL_ERROR

what happend ?

Error in the SAP Kernel

the current ABAP program "RSXMB_RESTART_MESSAGES" had to be terminated because the

ABAP process detected the internal error.

Please help me how to resolve this. How can i delete the errors.

Regards

Upendra.V