Invisimail mangles non-mailto link containing email address

We have a special case where our Bedework calendar outputs URLs like:

http://calendar.yale.edu/cal/linguistics/month/20130107/All/CAL-2c9cb3cc-3adcd7e8-013b-66706cd9-000050aebedework@yale.edu/

The URL contains 'bedework@yale.edu' at the end. Invisimail is acting on them, mangling and outputting code like this:

<p><a href="http://d7/%3Ca%20href%3D">//calendar.yale.edu/cal/linguistics/default/today/default/CAL-2c9cb3cc-3adcd7e8-013b-66706cd9-000050aebedework@yale.edu</a>/&#8221; rel=&#8221;nofollow&#8221; target=&#8221;_blank&#8221;>Kevin Ryan Talk</p>

Disabling the Invisimail filter prevents this from happening, but this is not ideal since email addresses aren't being obfuscated. Thanks.