Html form that auto fills outlook to,subject,body

I want to have a webpage that will automatically fill in the users to:email address Subject info and body message. The user will fill out a form on-line when they click send it will open there outlook or groupwise with the info from the for already posted in it. Below is a working example. My problem is I can only get the form to work with one body field I need a few body fields. Can anyone help? Thank you

<form>
To: <input type="text" id="mTo" /><br />

Subject: <input type="text" id="mSubject" /><br />

<textarea id="mBody"></textarea><br />

<input type="button" value="Send" onclick="document.location.href='mailto:'+document.getElementById('mTo').value+'?subject='+document.getElementById('mSubject').value+'&amp;body='+document.getElementById('mBody').value" />

&lt;/p&gt;