Everybody that posts on these forums is responsible for knowing and following the rules. The forum rules are linked at the top of very page:
In addition to the regular forum rules there are a couple of specific Trading Rules that everyone needs to be aware of:
Virtual Items - these forums are to be used only for selling and trading virtual items from the Diablo II. The currency used for purchasing these items is game currency for Auctions, and other items from the game for Trades. Under no circumstances will real world money or items be used to purchase items at these forums.
Posting Items - You can post any legitimate items from games Diablo II. You can not post dupes, bugged or hacked items. Dupes, account trades, items gathered with the aid of any 3rd party program and dubious trades are all deleted, without consultation and in certain cases the member's account is terminated and the account holder banned from using these trade forums further. Furthermore, do not bid or make an offer on any such item. If you see a dupe it should be reported through the "Alert Admin" link on the item.
Again, pay particular attention to what I've bolded above. If you use any sort of 3rd party program while playing the game you are not allowed to use these trade forums, period. There is no "OK" 3rd party program in regards to trading your items on these forums.