Solution : https://service.sap.com/sap/support/notes/661276 (SAP Service marketplace login required)
Key words : 
system displays message, access control engine, ace rule checks, higher support packages, sales area data, sales area, 0 support package 03, partner portal, purchase order, customer shop
Related Notes : 
       
| 696262 | CRM 4.0 SP Stack 1/2004 (SAPKU40004): Release & Info. Note | 
| 677456 | SAPKU40003: Support Package 03 for CRM 4.0 |