[boost] What is trac doing and how do I stop it doing it??

Subject: [boost] What is trac doing and how do I stop it doing it??
From: Fletcher, John P (j.p.fletcher_at_[hidden])
Date: 2014-02-04 18:23:03

I am attempting to update a ticket and I am getting this:
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Captcha Error

Submission rejected as potential spam (Content contained 1 blacklisted patterns)

Trac thinks your submission might be Spam. To prove otherwise please provide a response to the following.

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I would not mind but there is nothing to respond to and what I have typed seems to be lost.

Where is there guidance on how to avoid this problem, please?

John