t/op/tr failing on EBCDIC Platform.

Hi

Can somebody enlighten me how the transliteration operator (tr//) is
supposed to work  on EBCDIC platform?
I am asking this question with reference to a test case in perl-5.8.6
i.e t/op/tr which is failing on EBCDIC platform

Here is the snipped of the test case
................
...............
# Tricky on EBCDIC: while [a-z] [A-Z] must not match the gap characters,
# (i-j, r-s, I-J, R-S), [\x89-\x91] [\xc9-\xd1] has to match them,
# from Karsten Sperling.

# Not working in EBCDIC as of 12674.
$c = ($a = "\x89\x8a\x8b\x8c\x8d\x8f\x90\x91") =~ tr/\x89-\x91/X/;
is($c, 8);
is($a, "XXXXXXXX");
   
# Not working in EBCDIC as of 12674.
$c = ($a = "\xc9\xca\xcb\xcc\xcd\xcf\xd0\xd1") =~ tr/\xc9-\xd1/X/;
is($c, 8);
is($a, "XXXXXXXX");
.......
........

Is it supposed to change the gapped characters to X also? In that case
what is the behaviour for tr/a-z/X ?

Thanks in advance
Sastry