May I suggest that a) the "permission denied" error message is improved to say what exactly the problem is (it doesn't even tell you you're linking to a "forbidden" site, much less which one), that b) Wikipedia is added to the whitelist (shortcuts nonwithstanding, I see no issue with linking to Wikipedia using regular a tags), and c) that the bullet points below the "comment on" form, when listing approved HTML tags, caution that a is restricted in its use?

I'm pretty sure that these were anti spam measures, which is a hard fight when dealing with anonymous posts. Codifying all measures in written text makes it even harder.

All other boards I know solve this by simply disallowing anonymous posts.

So the natural reaction to your requests are:

Why don't you get a login?

Cheers Rolf
_{(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}