php 5.1.2 and mysql 5.0.18 problem: "Lost connection to MySQL server during query"

Hello! I tried to compile a LAMP system, but I'm having troubles in making MySQL and Apache+PHP to communicate: I've compiled apache-2.2.0, and, as the title says, mysql-5.0.18 and php-5.1.2. The ./configure options I passed when building mysql-5.0.18 are: export CFLAGS="-O2 -march=i486 -mtune=i686" export CXXFLAGS="-O2 -march=i486 -mtune=i686" ./configure \ --prefix=/usr \ --localstatedir=/var/lib/mysql \ --enable-assembler \ --enable-thread-safe-client \ --with-mysqld-user=mysql \ --without-debug \ --with-openssl=/usr \ --with-extra-charsets=all \ --with-unix-socket-path=/var/run/mysql/mysql.sock \ --with-big-tables \ --without-bench \ --program-prefix="" \ --program-suffix="" The ./configure options I passed to PHP are: export CFLAGS="-O2 -march=i486 -mtune=i686" export CXXFLAGS="-O2 -march=i486 -mtune=i686" ./configure \ --prefix=/usr \ --with-apxs2=/usr/sbin/apxs \ --enable-force-cgi-redirect \ --enable-discard-path \ --enable-fastcgi \ --with-config-file-path=/etc/apache \ --enable-safe-mode \ --with-openssl=/usr \ --with-zlib=/usr \ --with-zlib-dir=/usr \ --enable-bcmath \ --with-bz2=/usr \ --enable-calendar \ --with-curl=/usr \ --with-curlwrappers \ --enable-dba \ --with-gdbm=/usr \ --with-db4=/usr \ --with-inifile \ --with-flatfile \ --enable-dbase \ --with-libxml-dir=/usr \ --enable-exif \ --enable-filepro \ --enable-ftp \ --with-openssl-dir=/usr \ --with-gd \ --with-jpeg-dir=/usr \ --with-png-dir=/usr \ --with-zlib-dir=/usr \ --with-t1lib=/usr \ --enable-mbstring \ --with-libmbfl \ --with-mhash=/usr \ --with-mysql=shared,/usr \ --with-zlib-dir=/usr \ --enable-embedded-mysqli \ --with-ncurses=/usr \ --enable-shmop \ --with-libxml-dir=/usr \ --enable-soap \ --with-libxml-dir=/usr \ --enable-sockets \ --enable-sqlite-utf8 \ --with-regex=php \ --enable-sysvmsg \ --enable-sysvshm \ --enable-wddx \ --with-libxml-dir=/usr \ --with-pear \ --with-zend-vm=CALL \ --with-tsrm-pthreads \ --enable-shared \ --enable-static \ --program-prefix="" \ --program-suffix="" After the compilation and installation of the 2 packages, I added to the php.ini file the line "extension=mysql.so" and added the php module to the LoadModule section of the httpd.conf file. I logged as root to the mysql user and created the database cluster with mysql_install_db . Then I started the httpd and mysql servers. As the user mysql, I logged to the mysql server database with "mysql --user=root mysql" and I created a user with "GRANT ALL PRIVILEGES ON *.* TO 'myuser'@'localhost' IDENTIFIED BY 'mypass' WITH GRANT OPTION;". I put in the apache DocumentRoot the test.php file containing the following php directives: <?php // connect to the database; otherwise exit and return an error mysql_connect('127.0.0.1','myuser','mypass') or die(mysql_error()); ?> When I connect to the localhost, I got the message "Lost connection to MySQL server during query". If I substitute 'localhost' to '127.0.0.1' in the mysql_connect call, I get the following output: "Can't connect to local MySQL server through socket '/var/run/mysql/mysql.sock' (13)", but the file /var/run/mysql/mysql.sock exists! Did I miss something that needed to be done to make mysql and php to communicate? Thank you very much in advance. Best regards, Filippo