What kind of trouble are they having? This was obviously designed to curb spam, as there were quite a few guilds getting auto-app-spammed before this was implemented.
My first guess would be can't read. Your design like most allows a link that says "unreadable?" and only changes to a new pattern. I was using a site with a similar antispam security feature and when you clicked unreadable it popped up a little embedded player like quicktime or media player and spoke the pattern. Just to throw that in.
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Six Demon BagJack Burton: Hey, what more can a guy ask for?
Egg Shen: Oh, a six-demon bag!
Jack Burton: Terrific, a six-demon bag. Sensational. What's in it, Egg?
Egg Shen: Wind, fire, all that kind of thing!