Date Field Looks wrong

I just add a field into my registration form, i call it"birthday" field and set it up as date field. the problem is the date field look like a normal plain text field..
can anybody solve this?
I using joomla 1.7.2, CB 1.7, and cirrus-green template from hurricane media

you can see the problem at : yourswrites.com/component/comprofiler/registers.html

looks just fine in firefox.