Text-decoration is outside block element when text is justified

Here is sample text. As you can see after every line-break, some text-decoration is outside element

I have block element div with limited width (100px). Text inside is underlined. Some from that lines are out of element, what is wrong. That line can be outside much more than in this sample. It depends on text length.
Text-decoration in this case is working correctly only in IE.

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