Solution : https://service.sap.com/sap/support/notes/546414 (SAP Service marketplace login required)
Key words : 
commitment single line item, 0   <initial>   <initial>pfkber      <initial>, 0   <initial>  <initial>geber        <initial>, 0   <initial>   <initial>pgeber      <initial>, 0   <initial>  <initial>grant_nbr    <initial>, 0   <initial>   <initial>pgrant_nbr  <initial>, single line item report, commitment line item report, line item report, text fieldfkber        <initial>
Related Notes : 
       
| 896531 | CO-EP reports: Customer-specific authorization checks | 
| 659444 | Co-EP reports: Fields w/ funds & functions too short | 
| 634514 | Necessary notes for a productive start with EA-PS 2.0, SP0 | 
| 459730 | Missing columns in line item reports | 
| 359691 | CO line item reports: Missing fields | 
| 327821 | CO line item reports: fields are not filled | 
| 325546 | CO line item reports: Creating a user-defined field |