my $variable;

# First, save away STDERR
open SAVEERR, ">&STDERR";
close STDERR;
open STDERR, ">", \$variable or die "What the hell?\n";

# Now print something to STDERR, redirected to $variable
print STDERR "This is a test.\n";

# Now close and restore STDERR to original condition.
close STDERR;
open STDERR, ">&SAVEERR";


# Now test to see if $variable actually received the text.
print "Now for the real test.\n";
print $variable;