If it's essential to the operation of your web site, try harder to convince them. Having a fully configured perl installation is far better than the hack I'm about recommend. Failing that...

You can 'tweek' the Makefile.PL at the command line level to install the module into a custom directory, if you have access to one.

perl Makefile.PL PREFIX=<mydir>
make && make install
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Then you set the PERL5LIB environmental variable to point to this directory:

export PERL5LIB=$PERL5LIB:<mydir>/lib:<mydir>/lib/site_perl

OR

setenv PERL5LIB $PERL5LIB:<mydir>/lib:<mydir>/lib/site_perl
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I'm not sure, but this might work, in your script you can tweek the env PERL5LIB variable BEFORE the first 'use' statement

$ENV{PERL5LIB}=$ENV{PERL5LIB}::<mydir>/lib:<mydir>/lib/site_perl

use Digest::MD5 ;
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