Bizarre problem: pages that don't exist actually do

[Alan Burlison]

I've set up a new JSPWiki instance and initially it was working fine, 
but now I'm getting a lot of "nonexistent page" underlines on page 
links, when I click on the links I get a "This page does not exist. Why 
don’t you go and create it?" page, but if I actually click on the link 
to create the page, the "nonexistent" page content appears in the editor!!!

What gives?
Thanks,

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Alan Burlison
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