mail scored 6.5 points lead to autolearn=spam

[Philipp Snizek, seaan.net ag]

Hi

X-Spam-Status: Yes, score=6.5 required=3.0
tests=BAYES_50,INVALID_DATE,
        
MSGID_FROM_MTA_ID,NO_REAL_NAME,RCVD_IN_NJABL_DUL,RCVD_IN_SORBS,
        RCVD_IN_SORBS_DUL,TW_KT,URIBL_AB_SURBL,URIBL_SBL
autolearn=spam 
        version=3.0.1

I thought the autolearn=spam is at a score of 12. 
What are the reasons that it still is autolearned?

thank you
Philipp