jQuery add newline if text is wider than div

[circuiteater]

I add text to a div with the following jQuery code:\[code\]jQuery("div").text('some lorem ipsum');\[/code\]The div has a maximum width of 400px set by css. If I enter a text which is longer than 400px and has no whitespace, the text will not get breaked down into a new line. Instead it overflows the div which I dont want. How can I solve it, that this text withouth whitespace is breaked down after 400px to a new line?