Which version of Webinator are you using? It is possible that this might occur if you are using the -unique option, and it comes across a duplicate page.
It is a warning message, rather than an error. You may not get it on all duplicate pages. Are you using commercial or free Webinator. Which operating system?
Actually, my version is 2.55 -- I apologize for not specifying this in my previous post. When I said 2.5, I was basing it on the title page of the Webinator manual. I have just double-checked it on the server, and I have version 2.55, release: 20000120
Hopefully you're not using Webinator 2.5 and gw at all at this point. What error are you getting and what version of what product are you using and what are you doing when you get the error message?