[Plugin: Visual Form Builder] Localization (spanish)

Hi there. I’ve just updated the plugin to version 2.2 and I was happy to find a Spanish translation included, which is great!
But ther’re some missing strings that are not translated, and which are not in the visual-form-builder.pot file. These lines are:

• all validation texts (like “Please enter a valid email address.” or “Please enter only digits.”
• mounth and days names from calendar

I’ve found the phone validation text in the file visual-form-builder-validate.js but I know that code editing is no the best way to proceed.

What should I do to translate missing lines?

Thanks!

http://wordpress.org/extend/plugins/visual-form-builder/