XUBNAME field in table BUT000 is not updating with lastest userid

Hi ,

I'm creating employe Bussiness partners in CRM from R/3 through PFAL . 

I have an issue that when ever change in userid in pa0105 infotype in R/3 , change is not affecting in XUBNAME field in BUT000 table in CRM .changes for other fields are affecting.XUBNAME field in table BUT000 is not updating with lastest userid .Changes are affecting BP transaction . i'm using FM : BAPI_BUPA_CENTRAL_CHANGE for changes/updation of BPs .

Please suggest the solution ...

Thanks

Naveen