How to install skype for ios version 3.1.3 ?

This is an important question that how to make skype run on iPhone 3g or 2g running on ios firmware 3.x...
----if you are not jailbroken then
1)download old version skype from internet from legal old skype keeping sites
2)or just jailbreak using snowbreeze as shown in earlier posts
----if you are jailbroken
1)download installous from cydia
To download first add repo in cydia i.e.cydia.hackulo.us  ; then search installous and install it throught cydia
2)after downloading installous :::open it and search the software like skype and then download the older version of skype while choosing links then it will download them
3)at last step install it then you are ready to serve
*if anything problem about this let us know just post a comment*