Firefox: vertical-align: baseline stops working when using overflow: hidden

HTML

<span class="label">Label:</span>
<span class="block">Block with content, which can be quite long.</span>
<br>
<br>
<text class="block">WTF Man!</text>

CSS

body  { font-family: sans-serif }
.block {
    width: 10em; padding: .3em 0 .1em 0;
    overflow: hidden;
    white-space: nowrap;
    display: inline-block;
    border: 1px solid #666; background-color: #eee;
}