咨询PHP安装问题

安装PHP.51.1,运行./configure --prefix=/usr/local/php --with-apxs2=/usr/local/apache2/bin/apxs --with-jpeg-dir=/usr/local --with-png-dir=/usr/local --with-gd=/usr/local --enable-trace-vars --with-zlib-dir=/usr/local -with-mysql=/var/lib/mysql后,不能make,提示如下:
[root@localhost php-5.1.1]# make
make: *** No targets specified and no makefile found.  Stop.
[root@localhost php-5.1.1]# make install
make: *** No rule to make target `install'.  Stop.
我是新手,请帮忙解决.谢谢!


备注:我是按http://www.linuxeden.com/forum/t136344.html来安装　　　　　　

./configure 末尾的输出有什么报错？　　　　　　

末尾的输出:
Configuring extensions
checking whether to enable LIBXML support... yes
checking libxml2 install dir... no
checking for xml2-config path... /usr/bin/xml2-config
configure: error: libxml2 version 2.6.11 or greater required.　　　　　　

OK! :p  :p  :p