This error does still exist in B5.

I think that I know see the reason to why this goes wrong in the import, and that is that the code for the post looks to be "wrong". Instead of the normal "code" tags some html code is there. For the "Fair enough, Bill" the code looks like this:
Code
<blockquote>
<font size="1" face="Verdana, Helvetica, sans-serif">
quote:</font><hr />
<font size="2" face="Verdana, Helvetica, sans-serif">
Fair enough, Bill</font><hr />
</blockquote>
<font size="2" face="Verdana, Helvetica, sans-serif">
 </font>

My guess is that it should look like this, in order to import correct.
Code
[code]Fair enough, Bill[ /code]
(one space inserted on the end tag above in order for it to list correct)

Why there is some html code in the post, I have no idea. I looks OK in classic...