Topic: Forum to small

My forum is built in my website (see: www.bendevannijvel.com/forum/index.php), and my website is 740px wide. So sometimes, when a title is to long, you get this effect :

http://i20.servimg.com/u/f20/11/22/12/24/forum10.jpg

How can I change it so the title is on one line and not one two lines?