Can not get textarea to clear with onclick

I am using the script below to submit information to the database. I am trying to clear the textarea as well as the file input with the onclick event as I want to keep the other hidden field value. For some reason it will not clear at all and I am not sure why..Any help would be greatly appreciated..Thanks

<fieldset>
						<legend>Add Information</legend>
						
						<form action="scripts/ajaxupload1.php" method="post" name="standard_use" id="standard_use" enctype="multipart/form-data">
                         <p>Description:<br /><textarea name="description" id="description" rows="8" cols="80" /></textarea>
                         <script type="text/javascript">
			//<![CDATA[

				CKEDITOR.replace( 'description',
					{
						fullPage : true
					});

			//]]>
			</script>
                       <input type="hidden" name="entryid" value="<?php echo ''.$_GET['id'].'' ?>" /></p>
							<p><input type="file" name="filename" id="filename" /></p>
							<button onclick="ajaxUpload(this.form,'scripts/ajaxupload1.php?filename=filename&amp;maxSize=9999999999&amp;maxW=1000&amp;fullPath=http://www.tristatefoliagewonder.com/new_site/uploads/&amp;relPath=../uploads/&amp;colorR=255&amp;colorG=255&amp;colorB=255&amp;maxH=1000','upload_area','File Uploading Please Wait...&lt;br /&gt;&lt;img src=\'images/loader_light_blue.gif\' width=\'128\' height=\'15\' border=\'0\' /&gt;','&lt;img src=\'images/error.gif\' width=\'16\' height=\'16\' border=\'0\' /&gt; Error in Upload, check settings and path info in source code.');document.standard_use.description.value='';return false; ">Upload Image</button>
						</form>
					</fieldset>

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