my %vars = {};
    my $tt = Template->new({
        ABSOLUTE => 1,
        VARIABLES => {
            stylesheet => $Color,
            title => $Title,
            loginid => $username, 
            userid => $userid,
            lang => $sesslang,
        },  
    });
    
    # Sprache einbinden
    for (keys %lang) {
        #print "Add $_ with $lang{$_}{$sesslang} for Sessionlang $sesslang <br>";
        $vars{"lang_$_"} = $lang{$_}->{$sesslang};
    }

[...]

$tt->process($Template, \%vars ) || die "Template process failed: ", $tt->error(), "\n";