Any modification of siteconf generates errors that its not recognized as an internal or external command.

'siteconf' is not recognized as an internal or external command,
operable program or batch file.
NMAKE : fatal error U1077: 'siteconf' : return code '0x1'
Stop.
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I hadn't focused too much on that one, but I'll see what I can find out there. siteconf seems to be a Perl file.

# Guess values for system-dependent variables and create Makefiles.
# Generated by GNU Autoconf 2.53 and edited for this module 9-22-03

...

# the command line must contain
#
#    siteconf CCname Cfile_ext OBJext EXEext "Cflags" "LDflags"
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This is actually located in NetAddr-IP-4.007\Lite\Util if you look at the expanded package.