"Read" gives me for some reason a problem with some particular byte - I didn't had the time to isolate it.

Are you sure that binmode is enabled?

Both ...

open my $fh,'<:raw',$filename or die "Could not open $filename: $!";
my $data=do { local $/; <$fh> };
[download]

... and ...

open my $fh,'<',$filename or die "Could not open $filename: $!";
binmode $fh;
my $data=do { local $/; <$fh> };
[download]

... should do the trick. The first one requires a perl with support for I/O layers (introduced somewhere in the 5.8.x series, IIRC), the second one should also work with older perls. And this one is for really ancient perls:

local *FH;
open FH,"<$filename" or die "Could not open $filename: $!";
binmode FH;
my $data=do { local $/; <FH> };
[download]

See also Using ":raw" layer in open() vs. calling binmode() and PerlIO.

Alexander