I have never used the modules I mentioned - I just know that other people have suggested using them for their Date/Time processing needs. But since you asked, I installed them, and threw the following together, which works:

#!/usr/bin/perl -l

use Date::Calendar::Profiles qw( $Profiles );
use Date::Calendar;

my $cal = Date::Calendar->new( $Profiles->{US} )
    or die "no calendar\n";

my $days = $cal->delta_workdays(
    2004, 2, 11,   # first date
    2004, 2, 18,   # second date
    1,             # include first date
    0);            # exclude second date

print "days: $days";
[download]

The example prints the number of US workdays from Feb. 11, 2004 to Feb. 18, 2004, which is 4 (Presidents Day!).

HTH
--
edan (formerly known as 3dan)