I tried to print out all available PHP functions using 
get_loaded_extensions() and get_extension_funcs():
<?php
print("<h3>PHP" . phpversion() . "</h3>\n");
print("<ol>\n");
$ext = get_loaded_extensions();
sort($ext);
for($i = 0; $i < count($ext); $i++) {
	$name = $ext[$i];
	print("<li><b>$name</b>:</li>\n<ol>\n");
	$func = get_extension_funcs($name);
	sort($func);
	for($j = 0; $j < count($func); $j++) {
		
print("<li><code>$func[$j]()</code></li>\n");
	}
	print("</ol>\n");
}
print("</ol>\n");
?>
and this worked well with PHP4.0.3pl1.
However, since PHP4.0.4pl1/5, the Apache (1.3.19) 
subprocess dies:
[Sat May 12 14:26:49 2001] [notice] child pid 746 exit 
signal Segmentation fault (11)
When commenting out the get_extension_funcs() call, all is 
well. Even replacing the argument to a const (eg. 
get_extension_funcs("exif") ) works.
I tried to reproduce the error in a more simple way, but 
failed:
<?php
$name = "exif";
print_r(get_extension_funcs($name));
?>
works as expected. Still the script above fails.