Path to calling SSI file

I need to ask if someone know how to get access to the URL to the
calling .shtml file?

I found this
(http://blogs.msdn.com/david.wang/archive/2005/12/12/Child_URL_Execution_and_SSI_exec_Redux.aspx)
excellent blog explaining my problem but not with an answer. I can't
use SCRIPT_NAME env variable to get the path to my .shtml anymore.

I'm running Windows 2003 and ActivePerl 5.8.7.815.

/Jonas

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