configure: error: xml2-config not found. Please check your libxml2 installation.

检查是否安装了libxm2包

[root@localhost php-5.3.3]# rpm -qa | grep libxml2
libxml2-python-2.6.26-2.1.2.8
libxml2-2.6.26-2.1.2.8

重新安装libxml2和libxml2-devel包

[root@localhost Server]# yum -y install libxml2-*
Loaded plugins: rhnplugin, security
This system is not registered with RHN.
RHN support will be disabled.
server                                                   | 1.3 kB     00:00     
Setting up Install Process
Examining libxml2-2.6.26-2.1.2.8.i386.rpm: libxml2-2.6.26-2.1.2.8.i386
libxml2-2.6.26-2.1.2.8.i386.rpm: does not update installed package.
Examining libxml2-devel-2.6.26-2.1.2.8.i386.rpm: libxml2-devel-2.6.26-2.1.2.8.i386
Marking libxml2-devel-2.6.26-2.1.2.8.i386.rpm to be installed
Examining libxml2-python-2.6.26-2.1.2.8.i386.rpm: libxml2-python-2.6.26-2.1.2.8.i386
libxml2-python-2.6.26-2.1.2.8.i386.rpm: does not update installed package.
Resolving Dependencies
--> Running transaction check
---> Package libxml2-devel.i386 0:2.6.26-2.1.2.8 set to be updated
--> Finished Dependency Resolution

Dependencies Resolved

================================================================================
 Package        Arch  Version         Repository                           Size
================================================================================
Installing:
 libxml2-devel  i386  2.6.26-2.1.2.8  /libxml2-devel-2.6.26-2.1.2.8.i386   10 M

Transaction Summary
================================================================================
Install       1 Package(s)
Upgrade       0 Package(s)

Total size: 10 M
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing     : libxml2-devel                                            1/1 

Installed:
  libxml2-devel.i386 0:2.6.26-2.1.2.8                                           

Complete!

安装完之后查找xml2-config文件是否存在

[root@localhost Server]# find / -name "xml2-config" 
/usr/bin/xml2-config

如果存在就可以重新安装php了。