Configuring irssi for OS X Terminal

I don't think these questions are answered on the Web site.

OS X Terminal has 16 colors and bold and underline and blinking, all
separate from each other.  I have a terminfo file that describes
those features, so the "bold" escape sequence really prints as bold
now instead of brightening the color.  Is there a way to force irssi
to use the extra colors?  I just tried embedding an ANSI escape sequence
in one of the themable strings (prompt) and it is filtered out.

I'm also trying to use the terminal's scrollback instead of relying
on irssi's logging and scrollback.  Probably it's easy to create one
window and dump everything into that window (ircII works like that,
and works well).  Using more windows would be trickier, since I'd have
to force irssi to emit the right escape sequences that either put output
text in the scrollback or prevent it from being put there.  For example,
I might want the top window to go in the scrollback.  Right now, with two
windows, the bottom window's text can go in the scrollback, which is a
problem since the top window is also in the scrollback.   Has anyone
analyzed what escape sequences irrsi sends that affect scrollback?

Can I get an echo of commands I type, as well as their results?

Thanks,

-- Derek