Struts 1.3.5 and URL Validation

[pushkar . p]

Hi everyone,

I'm using Struts version 1.3.5 and I intend to use URL validation for a
field using the  validation.xml file. But, when I declare the field in
validation.xml, it does not validate the field to check whether the URL is a
valid one, meaning that it takes any input that I give in that textbox. 
Here's the entry from my validation.xml file:

<field property="vendorURL" depends="url">
        <arg key="form.vendor.VendorURL" position="0"/>
</field>

Is there anything else that I need to do for URL validation besides
declaring in validation.xml?

Regards,
Pushkar.