Combination of Apache 1.3.14, PHP4.0.3pl1 and libxml2-2.2.7.

PHP4.0.3pl1 fails to compile with libxml2-2.2.7 installed at the default directory /usr/local/lib or /usr/lib.
The line I used for compilation was:

./configure --enable-trans-sid --with-mysql --with-magic-quotes --with-apxs=/usr/local/apache/bin/apxs --with-dom --enable-wddx

Here is the error:

--------------
make[3]: Entering directory `/root/php-4.0.3pl1/ext/domxml'
/bin/sh /root/php-4.0.3pl1/libtool --silent --mode=compile gcc  -I. -I/root/php-4.0.3pl1/ext/domxml -I/root/php-4.0.3pl1 -I/root/php-4.0.3pl1/main -I/usr/local/apache/include -I/root/php-4.0.3pl1/Zend -I/root/php-4.0.3pl1 -I/usr/local/include -I/root/php-4.0.3pl1/ext/mysql/libmysql -I/root/php-4.0.3pl1/ext/xml/expat/xmltok -I/root/php-4.0.3pl1/ext/xml/expat/xmlparse -I/root/php-4.0.3pl1/TSRM  -DXML_BYTE_ORDER=12 -g -O2  -c php_domxml.c
php_domxml.c: In function `php_minit_domxml':
php_domxml.c:162: `XML_GLOBAL_NAMESPACE' undeclared (first use in this function)
php_domxml.c:162: (Each undeclared identifier is reported only once
php_domxml.c:162: for each function it appears in.)
make[3]: *** [php_domxml.lo] Error 1
make[3]: Leaving directory `/root/php-4.0.3pl1/ext/domxml'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/root/php-4.0.3pl1/ext/domxml'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/root/php-4.0.3pl1/ext'
make: *** [all-recursive] Error 1
-------------

Anomaly:

If I use --with-dom=/path/to/the/actual/libs I compile without an error, but PHP does not use the functions.

the phpinfo() tells me the dom and xml are compiled in, but none of the dom functions work.