Twitter Bootstrap Button Text Word Wrap
Try this: add white-space: normal; to the style definition of the Bootstrap Button or you can replace the code you displayed with the one below
<div class="col-lg-3"> <!-- FIRST COL -->
<div class="panel panel-default">
<div class="panel-body">
<h4>Posted on</h4>
<p>22nd September 2013</p>
<h4>Tags</h4>
<a href="#" class="btn btn-primary btn-xs col-lg-12" style="margin-bottom:4px;white-space: normal;">Lorem ipsum dolor sit amet, consectetur adipiscing elit.</a>
<a href="#" class="btn btn-primary btn-xs col-lg-12" style="margin-bottom:4px;white-space: normal;">Lorem ipsum dolor sit amet, consectetur adipiscing elit.</a>
<a href="#" class="btn btn-primary btn-xs col-lg-12" style="margin-bottom:4px;white-space: normal;">Lorem ipsum dolor sit amet, consectetur adipiscing elit.</a>
</div>
</div>
</div>
I have updated your fiddle here to show how it comes out.
You can simply add this class.
.btn {
white-space:normal !important;
word-wrap: break-word;
}