Upgrade bash,but bash --version no change,why

Question

For Shellshock issue I upgrade bash on redhat 4,5 use the follow steps

1. check bash version

   root@aaaA:/usr/src/redhat/RPMS/x86_64>bash --version GNU bash, version 3.2.25(1)-release (x86_64-redhat-linux-gnu) Copyright (C) 2005 Free Software Foundation, Inc.

2. upgrade bash

   rpmbuild --rebuild -bb bash-3.2-33.el5_11.4.src.rpm
cd /usr/src/redhat/RPMS/x86_64/
root@aaa:/usr/src/redhat/RPMS/x86_64>rpm -Uvh bash-* Preparing... ########################################### [100%] 1:bash ########################################### [ 50%] 2:bash-debuginfo ########################################### [100%]

3. check bash version again

root@aaa:/usr/src/redhat/RPMS/x86_64>bash --version GNU bash, version 3.2.25(1)-release (x86_64-redhat-linux-gnu) Copyright (C) 2005 Free Software Foundation, Inc.

4. reboot and check bash version again

root@aaa:/usr/src/redhat/RPMS/x86_64>bash --version GNU bash, version 3.2.25(1)-release (x86_64-redhat-linux-gnu) Copyright (C) 2005 Free Software Foundation, Inc.

5. check rpm

root@aaa:/usr/src/redhat/RPMS/x86_64>rpm -qa | grep bash bash-3.2-33.4 bash-debuginfo-3.2-33.4

Why bash version no change to bash-3.2-33.4