Strange URIBL_SBL false positive?

[Marco]

Hello,

 If I submit this to Spamassassin 3.3.2:

  <div><b>Da:</b> &lt;<a
href="mailto:ziop...@errebian.it";>ziop...@errebian.it</a>&gt;<br>;
   <b>Cc:</b> Alice &lt;<a
href="mailto:al...@errebian.it";>al...@errebian.it</a>&gt;,
   Bob &lt;<a href="mailto:b...@errebian.it";>b...@errebian.it</a>&gt;<br>;

I see:

 7.0 URIBL_SBL              Contains an URL listed in the SBL blocklist
                            [URIs: errebian.it]

...but errebian.it IPs are not in SBL..!

Could you help me to understand?
Thank you very much!!

Marco