When will the email SPPPPPPPPPPPPPPPPPPPPPP@domainname in Peoplesoft

I have noticed this in Peoplesoft FSCM 9.2 with Peopletools 8.53.14, in two places

1. in Supplier Registration (SUP_OB application package)

2. Requisition Sourced workflow email (PO_RQSRCD_WF application engine process)..

I think, in special conditions, this email gets substitutes the original user email..

I want to know whether this is a "Easter egg" in Peoplesoft

Trace from the PO_RQSRCD_WF application engine process below.. I replaced user name with ABCDEF1234 and actual domainname with domainname.. Rest all is coming from trace (including the Us at the beginning)

UUUUUUUUUUUUUUUUUUU:EOEN_Email

3637     14.45.15     0.000272                        Str[24]=GetEmailAddressFromOprID

3638     14.45.15     0.000249                        Str[10]=ABCDEF1234

3639     14.45.15     0.000304                    return value:

3640     14.45.15     0.000256                        SPPPPPPPPPPPPPPPPPPPPPP@domainname

Any ideas on how to prevent this?