Spam and definitely spam to Deleted Folder

I have been a very satisfied user of SpamSieve for some time on Tiger (no plans for Leopard) and Entourage.
I always (well, almost always) scan the Junk folder to review email marked Spam and Definitely Spam and have never found one so marked to be a good email.
Is there a way to automatically send these emails to the Deleted Items folder?

I’m not quite sure what you mean by “Definitely Spam” since that isn’t a category that SpamSieve uses by default. You can, however, make it treat Junk messages differently from Uncertain Junk ones.

Many of my emails in the Junk E-mail folder have {Spam} or {Definitely Spam}
appended to the beginning of the subject.
Is this not SpamSieves doing?

SpamSieve is not doing that. It’s probably due to a spam filter on your mail server. Since SpamSieve is probably already taking into account the analysis done by the server-side filter, I don’t recommend second-guessing it by moving or deleting messages based on the subject tags.