Fetching a page using LWP::UserAgent over https can truncate a long line, while the same page over http is fine.  Here is a recipe to reproduce the bug using only a Fedora installation (so both the web server and the client are on the same machine, which is running vanilla Fedora 10).  Please do try and see if you can reproduce the bug.

Install Fedora 10 (I used the i386 live CD and the 'install to local drive' option).  Change the firewall config so that HTTP and HTTPS connections are accepted and make sure Apache is running with SSL:

# yum install mod_ssl
# service httpd stop
# service httpd start

Now create a test file containing a long line of text:

# perl -E 'say "X" x 3059, " ", "X" x 21518' >/var/www/html/o.html

Note the filename o.html.  Not every filename triggers the bug.

Now you should be able to fetch <http://localhost/o.html> and <https://localhost/o.html> with Firefox or wget (after certificate warnings).  Of course, they both return the same content.  However, run this test program:

#!/usr/bin/perl
use warnings;
use strict;
use 5.010;
use LWP::UserAgent;
sub get_length {
    my $uri = shift;
    my $ua = LWP::UserAgent->new;
    die if defined $ua->max_size;
    my $req = new HTTP::Request(GET => $uri);
    my $res = (new LWP::UserAgent)->request($req);
    if (not $res->is_success) {
        my $err = $res->status_line;
        die "could not get Outlook web access page $uri:\n$err\n";
    }
    my $c = $res->content;
    return length $c;
}
my $https_l = get_length "https://localhost/o.html";
my $http_l = get_length "http://localhost/o.html";
die "lengths differ: $https_l vs $http_l\n" if $https_l != $http_l;

You will see that when fetched via https using LWP::UserAgent, the file is truncated.

This is a reasonably minimal test case.  If you're unable to reproduce it, let me know and I will try to get a better one.  If you can reproduce it on a clean Fedora 10 system (as I could) then we can start investigating where the bug lies.  It must be in some Fedora-maintained package, since both the web server and client are on the local machine.  But I suspect that Apache is not at fault, since I have seen the same truncation bug fetching https pages from non-Apache web servers.