Here is a semi-automatic solution:
\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{matrix,calc,calendar}
\newcommand{\ts}{\textunderscore}
\begin{document}
\begin{tikzpicture}
\foreach \x[count=\xi from 4] in {1,...,5} {
\node[anchor=north,text width=2cm,align=center,font={\tiny\sffamily}] (time\x) at (0,-\x cm) {\pgfcalendarmonthname{\xi} 2012};}
\matrix (m) at (2,-1) [
anchor=north west,
matrix of nodes,
nodes={font=\sffamily\tiny,inner sep=0},
row sep=1pt,
column sep=2mm,
column 2/.style={text width=9cm,align=left}
]{
0.00000 &entering nautilus-main.c:main()\\
0.00222 &nautilus-main.c calling gnome\ts program\ts init()\\
0.16386 &nautilus\ts application\ts instance\ts init() calling signal\ts connect\ts on\ts gnome\ts vfs\ts get\ts volume\ts monitor\\
1.16386 &nautilus\ts application\ts instance\ts init() finished signal\ts connect\ts on\ts gnome\ts vfs\ts get\ts volume\ts monitor\\
1.16386 &nautilus\ts application\ts instance\ts init() had enough of calling signal\ts connect\ts on\ts gnome\ts vfs\ts get\ts volume\ts monitor\\
2.56386 &nautilus\ts application\ts instance\ts init() enjoying the idle\ts CPU\ts time\\
2.57386 &nautilus\ts application\ts instance\ts init() enjoying the idle\ts CPU\ts time\\
2.58386 &nautilus\ts application\ts instance\ts init() enjoying the idle\ts CPU\ts time\\
2.59386 &nautilus\ts application\ts instance\ts init() enjoying the idle\ts CPU\ts time\\
};
\foreach \x in {4,5} {\draw (m-\x-1.west) --++(-2mm,0) -- ([xshift=5mm]$(time1)!0.2!(time2)$) --++(-5mm,0);}
\foreach \x in {6,...,9} {\draw (m-\x-1.west) --++(-2mm,0) -- ([xshift=5mm]$(time2)!0.5!(time3)$) --++(-5mm,0);}
\end{tikzpicture}
\end{document}

Basically, we just draw a month list downwards on the left without too much automation. Then, we also put a matrix next to it. Then the remaining part is drawing the connections and how many of them related to a particular date node is also defined manually. You can modify further to suit your needs.