Threads is required

Summary

How do I change the error messages put out by the FormSubmit widget?

Content

Hello,

When a user is on the submit a question form (Questions/detail.php) and submits an attachment without entering anything into the TextInput widget a mysterious and terribly confusing to our customers error message pops up stating "Threads is required"

I've searched all over the widget files, the customer portal PHP pages, the configuration settings and message base in OSvC and do not see how to change this message to be something less than cryptic. We get quite a few people submitting attachments without entering the thread information in the TextInput box. I'd simply like to change that error message to something more human friendly, like "Please describe why you are clicking the submit button." or something similar. How do I change that message?