How to get a core dump

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Hi everybody.
I have a problem on a production cluster with a somewhat big mod_perl
app, and I just cannot get any clue of what is happening.

The problem is that the servers just exit with Segmentation fault
randomly.  
The problem is rare, hapens 10/20 times each day in each of the 6
frontends, which globaly processes about 1.000.000 daily hits.
The global stats show about 30 Internal server errors daily, I don't
know if a segfault can cause an Internal Server Error on the client (I
suppose not, if the server dies, cannot send the 505), but the numbers
don't match anyway.

I think a coredump will help me understand why it segfaults, but I don't
know how to make apache dump a coredump, I've tried a lot of recipes
found on internet with any success. Making things more complicated, this
problems only happens on the production systems, (Suppose only on some
pages...) so I cannot reproduce it on my test system.

So, my question is... There is any way to force apache to dump a
coredump file? I suppose I'm forgotting something but I really
desperate...

A secondary question is, some of the servers transforms all UTF8 strings
with "garbage" when some Segfault happens (Seems like double-encoded
UTF8, the page shows 3 or 4 chars for every UTF8 char...). The only way
to solve this is reboot the machine completely.
Is that related to this same problem? Or is an obscure UTF8 perl/Apache
problem?

Many thanks, 
I'm using mod_perl 1.29 with apache 1.3.31. 
My perl conf:

Summary of my perl5 (revision 5.0 version 8 subversion 0) configuration:
  Platform:
    osname=linux, osvers=2.4.20-2.48smp,
archname=i386-linux-thread-multi
    uname='linux str'
    config_args='-des -Doptimize=-O2 -march=i386 -mcpu=i686 -g
-Dmyhostname=localhost -Dperladmin=root@localhost -Dcc=gcc -Dcf_by=Red
Hat, Inc. -Dinstallprefix=/usr -Dprefix=/usr -Darchname=i386-linux
-Dvendorprefix=/usr -Dsiteprefix=/usr
-Dotherlibdirs=/usr/lib/perl5/5.8.0 -Duseshrplib -Dusethreads
-Duseithreads -Duselargefiles -Dd_dosuid -Dd_semctl_semun -Di_db
-Ui_ndbm -Di_gdbm -Di_shadow -Di_syslog -Dman3ext=3pm -Duseperlio
-Dinstallusrbinperl -Ubincompat5005 -Uversiononly -Dpager=/usr/bin/less
-isr'
    hint=recommended, useposix=true, d_sigaction=define
    usethreads=define use5005threads=undef'
 useithreads=define usemultiplicity=
    useperlio= d_sfio=undef uselargefiles=define usesocks=undef
    use64bitint=undef use64bitall=un uselongdouble=
    usemymalloc=, bincompat5005=undef
  Compiler:
    cc='gcc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS
-DDEBUGGING -fno-strict-aliasing -I/usr/local/include
-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/gdbm',
    optimize='',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -DDEBUGGING
-fno-strict-aliasing -I/usr/local/include -I/usr/include/gdbm'
    ccversion='', gccversion='3.2.2 20030213 (Red Hat Linux 8.0
3.2.2-1)', gccosandvers=''
gccversion='3.2.2 200302'
    intsize=e, longsize= , ptrsize=p, doublesize=8, byteorder=1234
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
    ivtype='long'
k', ivsize=4'
ivtype='long'
known_ext, nvtype='double'
o_nonbl', nvsize=, Off_t='', lseeksize=8
    alignbytes=4, prototype=define
  Linker and Libraries:
    ld='gcc'
l', ldflags =' -L/usr/local/lib'
ldf'
    libpth=/usr/local/lib /lib /usr/lib
    libs=-lnsl -lgdbm -ldb -ldl -lm -lpthread -lc -lcrypt -lutil
    perllibs=
    libc=/lib/libc-2.3.1.so, so=so, useshrplib=true, libperl=libper
    gnulibc_version='2.3.1'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so', d_dlsymun=undef, ccdlflags='-rdynamic
-Wl,-rpath,/usr/lib/perl5/5.8.0/i386-linux-thread-multi/CORE'
    cccdlflags='-fPIC'
ccdlflags='-rdynamic -Wl,-rpath,/usr/lib/perl5', lddlflags='s
Unicode/Normalize XS/A'


Characteristics of this binary (from libperl):
  Compile-time options: DEBUGGING MULTIPLICITY USE_ITHREADS
USE_LARGE_FILES PERL_IMPLICIT_CONTEXT
  Locally applied patches:
        MAINT18379
  Built under linux
  Compiled at Feb 18 2003 22:19:53
  %ENV:
    PERL5LIB="/usr/eBD/perl"
  @INC:
    /usr/eBD/perl/i386-linux-thread-multi
    /usr/eBD/perl
    /usr/lib/perl5/5.8.0/i386-linux-thread-multi
    /usr/lib/perl5/5.8.0
    /usr/lib/perl5/site_perl/5.8.0/i386-linux-thread-multi
    /usr/lib/perl5/site_perl/5.8.0
    /usr/lib/perl5/site_perl
    /usr/lib/perl5/vendor_perl/5.8.0/i386-linux-thread-multi
    /usr/lib/perl5/vendor_perl/5.8.0
    /usr/lib/perl5/vendor_perl
    /usr/lib/perl5/5.8.0/i386-linux-thread-multi
    /usr/lib/perl5/5.8.0






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