You can easily resize the layout of the messages, unfortunately there is not much visual feedback:
move the mouse over the chatlines from left to right until you notice the mouse cursor change to a "hand" icon. Click and hold the left mouse button and move the mouse around to adjust the spacing. There are a total of 2 these invisible handles: one for adjusting the position of the nicks relative to the timestamp and one for the position of the messages relative to the nicks.
