How to change my phone model if i have root access? I have rooted my phone and changed the os with CM9.X.

My phone name was Sony Xperia MINI sk17i. after installing of new os then model name has been changed. 

So i want to change this this to that name. I have terminal app &amp; have root access how can i do that, Please advice me.
WARNING: Messing with your build.prop file can have serious repercussions to your ROM. It is a very 'sensitive' file and can cause unforseen consequences. Doing any of the below is done at your own risk. ALWAYS make a nandroid backup before messing with a ROM. I learned this the hard way, don't do what I did! 



This should work, though it depends on CM9:

Download Root Explorer for your phone. 


Open root explorer, go to /system, and Search Build.prop
Open with text Editor 
Search your baseband and device model
Don't edit anything except baseband, custom ROM and device model.
Reboot
Look in Settings → About


EDIT: Here is an alternative method for doing the same using ES file explorer. I haven't tested this myself, but it has more detail for a beginner. See XDA Developers forum.

EDIT 2: build.prop Editor is an app to modify your build.prop directly. I have NOT tested this either so use at your own risk. Link to source code in the description in the play store.