The require statement will be interpreted the same whether PERL.EXE was invoked to run the script from IIS, Apache, a command line, etc. It'll always look for the file being required in the paths defined in the @INC array, and IIS can't do anything to change that. I use require and IIS all the time, and never include the path to the file being required. The web server is kind of "out of the loop" at that point. Unless by 'require' you don't mean PERL'S require statement, but something entirely different.

Do you maybe mean that its behavior is different when referencing files in VIRTUAL directories, somehow?