RewriteEngine on

RewriteMap   lowercase  int:tolower

# allow CGIs to work
RewriteCond  %{REQUEST_URI}  !^/cgi-bin/

# check the hostname is right so that the RewriteRule works
RewriteCond  ${lowercase:%{SERVER_NAME}}  ^www\.[a-z-]+\.isp\.com$

# concatenate the virtual host name onto the start of the URI
# the [C] means do the next rewrite on the result of this one
RewriteRule  ^(.+)  ${lowercase:%{SERVER_NAME}}$1  [C]

# now create the real file name
RewriteRule  ^www\.([a-z-]+)\.isp\.com/(.*) /home/$1/$2

# define the global CGI directory

ScriptAlias  /cgi-bin/  /www/std-cgi/