What a shame that you can't get it to work over two lines! Would be awesome if the element was display block and had a height set to 2em or something, and when the text overflowed it would show an ellipsis!
For a single liner you can use:
.show-ellipsis {
overflow: hidden;
text-overflow: ellipsis;
white-space: nowrap;
}
For multiple lines maybe you could use a Polyfill such as jQuery autoellipsis which is on github http://pvdspek.github.com/jquery.autoellipsis/