reading the docs for Net::FTPSSL, I see there is an option for explicit encryption called EXP_CRYPT that you pass in new. Maybe you can try to put it "explicitly" although it is supposed to be the default.

the example in the synopsis does that:

my $ftps = Net::FTPSSL->new('ftp.yoursecureserver.com', 
                              Port => 21,
                              Encryption => 'E',
                              Debug => 1) 
    or die "Can't open ftp.yoursecureserver.com";
[download]

hth --stephan