jQuery UI can do the exact style you want. (and functionality)
You need to download the jQuery UI script and the Smoothness theme (visit http://jqueryui.com/download/ and select Kernel and datepicker using the radio buttons and smoothness from the drop-down list to the right)
HTML
<div id="datepicker"></div>
Javascript
var activeDays=[1,4,10,21,22,23,27,28,30]; $('#datepicker').datepicker( { beforeShowDay: function(date) { var hilight = [false,'']; if ( activeDays.indexOf( date.getDate() ) > -1) { hilight = [true,'isActive']; } return hilight; } } );
The activeDays variable can contain dates directly (and not just the day number), and you will need to change the conditional expression inside the function to check the match.
isActive is a class used to control the style of active dates.
.isActive a.ui-state-default{ background:none; background-color:pink; }
Live example http://jsfiddle.net/gaby/C95nx/2/
the above code and example are displayed as

Gaby aka G. petrioli
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