Xperia Mini ST15i Root

Rooting 4.0.4 build version 4.1.B.0.587 & 4.1.B.0.531 ICS ST15i
Xperia Mini ST15i which has build version 4.1.B.0.587 with ICS.

here download 
flashtool_
 hotfile

stoke kernel of st15i_
mediafire

kernel of st15i_
mediafire

rooting toolkit_
http://www.4shared.com/zip/mzM0gROA/DooMLoRD_v1_Xperia-2011-ICS-RO.html?refurl=d1url

1: First of all go to Phone settings>Developer options>USB debugging and mark it check
2: Now again go to phone settings>Xperia>connectivity settings>MSC mode and set it MSC mode, be sure you have not set the MTP mode.
Optional Phone settings>Display>screen timeout set it to at least 10 min (IMO its worth to set it 10 min).
3: Install the flashtool which will install in the C: drive. After installing it go to the following path

C:\flashtool\firmwares

4: Now delete all existed kernels/files in this folder and copy&paste the kernels which have you downloaded for ST15i & ST18i
5: Now click on flashtool.exe for 32-bit OS and flashtool64.exe for 64-bit OS. Now click on the flash icon for flash the kernel and select the Flashmode and click OK as shown in the screen shot below.

and select the kernel of ST18i which has the name ray in falshtool and click OK. After clicking OK a guide window will appear and ask you to Switch off your phone Connect your phone with USB while hold the volume down key (Guide shows the method for other devices while ST15i has to hold the volume down key)  If your phone driver installs successful then its good but if not don't worry go to C:\flashtool\drivers and run the exe and select the Flashmode drivers မႈရင္း website  http://android.stackexchange.com/questions/25065/how-to-root-the-xperia-mini-st15i