解决安装oracle11g r2时提示pdksh conflicts with ksh-20100621-2.el6.i686问题

在CenOS6、RHEL6或者ORACLE LINUX 6上安装oracle 11g R2的时候提示:pdksh包没有安装，

按照提示从网上下了个pdksh-5.2.14-36.el5.i386.rpm包，然后尝试安装：

# rpm -ivh pdksh-5.2.14-36.el5.i386.rpm
warning: pdksh-5.2.14-36.el5.i386.rpm: Header V3 DSA/SHA1 Signature, key ID e8562897: NOKEY
error: Failed dependencies:
pdksh conflicts with ksh-20100621-2.el6.i686