use strict; # =)

my %months = (		'English'=> ['January', 'February' ... ],
			'French'=> ['Janvier', 'Fevrier', ... ],
			'Italian'=> ['gennaio', 'febbraio', ...],
		#etc ...
	    );

##</code><code>##

# $language is set at run time and would be one of 'English', 
# 'Italian' etc. -- the keys of your $months hash
# also assumes $month_number ranges from 1 to 12; if it's 0 to 11, eliminate the '-1'

my $month_name = $month{$language}[$month_number-1];