Change before earliest retro. date .. acc. to control rec. to py area MO

Anyone have any ideas about where I might look to find what is causing this error?

Using ECC6 we are trying to transfer a person from one position to another position in the same Org Unit effective 09/01/2008 but we are getting this error:

Change before earliest retro. date 09/01/2007 acc. to control rec. to py area MO

We have the Earliest Retroactive date under Payroll/Retroactive Accounting on Infotype 0003 set to 09/01/2007. Realizing that the error message means that something is trying to happen before 09/01/2007 we have search through the PA data but have been unable to find anything. We have created new objects (Job, Position) attached to the person using the dates 09/01/2008 but still get the error.