所以我认为你的问题在于你函数中href中的引号。试着像这样逃离他们,它应该被修复。
<p><?php _e("Sorry but, you are looking for something that isn\'t here. <br /><br />
Looking for more web developer jobs, please visit our sister site: <a href=\\"http://LAMPjobsLA.com\\">LAMPjobsLA.com</a>", \'cleanhome\') ;?></p>