TOPIC: How to upgrade joomla comment?

Hei... i'm a noobz sure..

I use Joomla 1.015
A long time ago..I already installed com for joomla.. Joomlacomment 3.12b
And it works fine except the URL bug that start to bother me now.

So decide to install the latest joomlacomment..
But.. I dont know how to upgrade my version to the latest ver without losing all my firends comments

Can I upgrade? How?
Should I clean Install? should I backup first? How?

In my Joolacomment3.12b I only see the import.. and no export...

Please Help...

Thanx a lot