WordPress 1.5.1 category problem

Not usre if this is you guys or ECTO…

The problem:
I have 4 WordPress 1.5.1 categories (1,2,3,4 with 1 being the wordpress default). When I post using ECTO 2.3.3 to say category 3 then my post automatically shows up as category 1 PLUS category 3. I can’t just get a category 2,3 or 4 post on its own. I have tried adjusting this in ECTO using the tick boxes, deleting everything and starting again, but I can’t seem to just post to one catetgory at a time unless it is the wordpress default category.

BTW I can go to into my wordpress dashboard and post to a single category.

Thanks,
john