Get IDOC NUMBER After Submit to SAP

Hi all
Well, 1º my english is not got…
2º does any one know, how do i get the idoc number from BC after submit it to SAP?

i’ve tryed to use one RFC( SREL_GET_NEXT_RELATIONS ) but it is to slow, and im get this err: “2004-12-13 10:20:53 BRST com.sap.mw.jco.JCO$Exception: (104) RFC_ERROR_SYSTEM_FAILURE: Time limit exceeded.”

Is There Another Way to get the number or the IDOC STATUS???

Thanks ALL!