Excessive traffic pattern blocked and validation through home page *also* blocked

I am a teacher at a university.  I require my students to validate their
HTML using the W3C validator.  Today students on campus began getting
the message "Excessive traffic pattern blocked."

It is possible that someone has installed a "validate everything"
plugin; it is also possible that 80+ students are validating a page at a
time, but all behind the same gateway: 168.28.180.30.  I understand that
I should not contact the W3C about this because the restriction will be
removed when the pattern stops.

My real problem is this: The error page says, "You should still be able
to use the form interface on the Validator Home Page to check the page
by URL."  I am happy with telling my students they must use that
mechanism and no other.  However, attempting to validate through the
validator home page *also* produces the "Excessive traffic pattern
blocked" message.  Can this be fixed to allow one-at-a-time validations?

Best regards,
Bob Brown, Ph.D.

---
Senior Lecturer in Information Technology
Teacher of the Year, 2009-2010
College of Computing and Software Engineering
Mail Stop J-330
Kennesaw State University Marietta Campus
1100 South Marietta Parkway SE
Marietta, Georgia 30060-2855

(678) 915-7505
http://educate.spsu.edu/bbrown/
http://bbrown.spsu.edu/bbrown.vcf

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