[Koha] Koha Upgradation

[prasanth]

Dear All,

We are now using koha version 2.2.5 ( Koha version2.2.5

OS version ('uname -a')Linux prahari 2.6.9-78.0.8.ELsmp #1 SMP Wed Nov
19 20:05:04 EST 2008 i686 i686 i386 GNU/Linux

Perl version5.008005

MySQL versionmysql Ver 14.7 Distrib 4.1.22, for redhat-linux-gnu (i686)
using readline 4.3

Apache versionServer version: Apache/2.0.52 Server built: Nov 15 2008
03:52:33)

 and now we installing Koha version 3.2.5 but unable to transfer
database old version to new.How to upgrade my koha.Please help me. 

Regards
Prasanth
Librarian
Chintech
Kerala,India