Solution : https://service.sap.com/sap/support/notes/738950 (SAP Service marketplace login required)
Key words : 
sap_basis support package queue fails, transport object r3tr sdbp, exact error message stated, sap_basis support package, microsoft sql server, spam import broke, single spam queue, sql script sap_mon_sqlsetup, support package, spam queue
Related Notes : 
       
| 782140 | OCS: Known problems with Support Packages in Basis Rel. 6.20 | 
| 447925 | OCS: Known problems with Supp. Packages in Basis Rel.6.20 |