Hai, I would like to ask about how to upgrade mysql from 5.1 to 5.5 in webmin? I dont want to make any mistake for upgrading database, so I need some tutorials or suggestion before I start to upgrade mySQL. 
Howdy,
Unfortunately, there isn’t a supported way to change to a different MySQL version.
We always recommend using the MySQL version provided by your distro… using MySQL versions provided by a third party are frequent causes of problems.
If you’d like to use a different MySQL version, our recommended way of doing that is to migrate to a distribution that ships with that particular MySQL version.
-Eric