You look up SORBS data from the combined zone dnsbl.sorbs.net, but you pretend you're looking up data from each of the individual subzones. This has the effect that hosts listed on any SORBS subzone appear to be listed on all of the separate subzones you present, which is of course not true. If you are going to present results split across the subzones, you will also need to query all of the subzones individually to ensure correct results. See http://www.sorbs.net/using.shtml for the instructions.
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