Address subscribed twise: where's patch for MacOS X?

Hi!

I'm new in this ML.

Recentrly, I've installed qmail+vpopmail+qmailadmin+ezmlm+ezmlm-idx
on MacOS X 10.4.8.

Soon I had a trouble with adding several mail addresses to newly created
ML using qmailadmin.

In almost all casese, user mail addresses are subscribed twice.

And soon I've found the reason on some sites, those said
MacOS X file systems (HFS+) is "case-insensitive".

For example, if I
  % touch a
  % touch A
  % ls -la

then I get only file "a". This means MacOS treated "a" and "A" as same
file because of its case-insensitveness.

I also found that somebody would be going to write patch for this issue,
modifying hash algorithm of ezmlm. But eventually I could not find such a
patch anywhere.

I would really appreciate if somebody tell me URL where I can get patch
for MacOS X, or any other solutions for this case-insensitiveness issues.

Thank you.