A potentially dangerous Request.Form value was detected from the client

this is a .net 1.1 issue & IE6

i understand the reason for getting the above error message and what can be done to rectify it but it appears that XP & IIS5.1 handle this different to Win2003Server & IIS6

when i enter invalid/dangerous data into a textbox while running the project through the developement environment (IIS5.1 & XP) i get the error, but when i hit the website on the test server i dont get the error

there is no differences in code or config files between the 2, so im at a loss as to why the error does not occur on the win2k3 server & IIS6

Any ideas?
Cheers,
Craig
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