PHP configure line:
./configure --with-mysql --with-apache=../apache_1.3.4/   \
     --enable-track-vars --enable-debug

Apache configure line:
OPTIM="-O2" CFLAGS="-g" ./configure --prefix=/etc/apache  \
     --activate-module=src/modules/php3/libphp3.a    \
     --enable-module=rewrite

PHP is fresh CVS from about 1800 Feb 17 1999; Apache is fresh tarball 
just downloaded. The bug appeared using Apache 1.3.3 as well.

Script:
<?php
function foo() {
   echo "Just some stuff.<br>";
}
register_shutdown_function( 'foo' );
?>

Backtrace:
#0  0x400cf8f0 in memset ()
#1  0x80f3684 in include_names ()
#2  0x805f707 in str_free (ptr=0x8128558) at main.c:145
#3  0x80623b3 in _php3_hash_destroy (ht=0x80f3684) at php3_hash.c:637
#4  0x8060354 in php3_request_shutdown (dummy=0x0) at main.c:878
#5  0x80975ab in run_cleanups (c=0x81272f4) at alloc.c:1650
#6  0x809670d in ap_clear_pool (a=0x8125fb4) at alloc.c:475
#7  0x8096762 in ap_destroy_pool (a=0x8125fb4) at alloc.c:505
#8  0x80966fc in ap_clear_pool (a=0x8110b1c) at alloc.c:472
#9  0x80a059a in child_main (child_num_arg=0) at http_main.c:3616
#10 0x80a0aab in make_child (s=0x80f99fc, slot=0, now=919312756) at http_main.c:3924
#11 0x80a0ba3 in startup_children (number_to_start=3) at http_main.c:4004
#12 0x80a1033 in standalone_main (argc=4, argv=0xbffffcc4) at http_main.c:4291
#13 0x80a16d5 in main (argc=4, argv=0xbffffcc4) at http_main.c:4592