Dylan Hartley criticised Northampton's performance as "not good enough" after the Saints' Heineken Cup ambitions were all but extinguished by rampant Ulster.
Ulster secured a 25-6 bonus victory at Franklin's Gardens to inflict back-to-back European defeats on the Saints.
Northampton Saints and England hooker Dylan Hartley has been banned for eight weeks for biting an opponent
The RFU found him guilty of biting Ireland's Stephen Ferris during a Six Nations game earlier in March 2012.
The ban means he will be available for England's summer tour of South Africa, but will only play for Saints again this season if they reach the Aviva Premiership final.