The new lines are actually sent as CR/LF.
The background is one solid color.
Before hitting enter after the first few lines I switched the font back to "regular."

\rtf1\ansi\ansicpg1252\deff0\deflang1033{\fonttbl{\f0\fswiss\fprq2\fcharset0 Verdana;}{\f1\fmodern\fprq1\fcharset0 Courier;}}
{\colortbl ;\red0\green64\blue128;\red0\green0\blue255;\red255\green0\blue0;}
\viewkind4\uc1\pard\cf1\f0\fs20 regular\line\i italic\i0\par
\b bold\b0\par
\b\i bold italic\par
\b0\i0 regular again\par
\fs24 regular size 12\par
\i\fs32 bold size 16\par
\f1\fs30 courier italic size 15\par
\cf2\i0\f0\fs24 blue text, no (white) background\par
\cf3\b\fs20 red text green background\par
red text white background\par
Smileys: <##icqimage0000><##icqimage0004><##icqimage0008><##icqimage0005><##icqimage000d>*TIRED**THUMBS UP**IN LOVE**DRINK*\cf1\par