title: Custom form validation error message for Codeigniter 2
body: <p>I have a drop down named "business_id".</p>
  
  <pre><code>&lt;select name="business_id"&gt; 
      &lt;option value="0"&gt;Select Business&lt;/option&gt; More options... 
  &lt;/select&gt;
  </code></pre>
  
  <p>Here comes the validation rule, user must select an option.</p>
  
  <pre><code>$this-&gt;form_validation-&gt;set_rules('business_id', 'Business', 'greater_than[0]');
  </code></pre>
  
  <p>Problem being the error message says: The Business field must contain a number greater than 0. Not very intuitive! I want it to say "You must select a business".</p>
  
  <p>I tried:</p>
  
  <pre><code>$this-&gt;form_validation-&gt;set_message('Business', 'You must select a business');
  </code></pre>
  
  <p>But CI complete ignores this. Does anyone have a solution for this?</p>