Automatic hyphenation is managed through different CSS settings as it is a "new" CSS3 so every renderer tends to use a different one.
Set them for <body> and you should completely turn it off.
Some possible properties to disable:
Code:
body {
adobe-hyphenate: none;
hyphenate: none;
hyphens: none;
-moz-hyphens: none;
-webkit-hyphens: none;
}