From a 01/01/13 pull of Transunion via myFico:

Under "What's helping your FICO score"

1) There is no evidence of a serious delinquency (60 days past due or greater) or derogatory description on your credit report. 

Followed by in the box:

- Number of your accounts that were ever 60 days late or worse: 1 account 

The late payment is legit, so it's likely something in your report generation code that's gone a little wonky; or it's being looked at by age and mine is >2 years ago.  In either event more clarity or consistency would be a good thing I suspect.

---

Starting Score: EQ 561, TU 567, EX 599* (12/30/11, EX lender pull 12/29/11)
Current Score: EQ 660, Wally TU 697, EX unknown (05/13/13)
Goal Score: 680 in all three (01/01/14)

Take the FICO Fitness Challenge