Unable to root device

Hi guys, i'm new to this forum and to android rooting.
I followed the procedure to root the device but i'm getting this error:

==============================================
= =
= Easy Root Tool v12 =
= Supports various Xperia devices =
= created by zxz0O0 =
= =
= http://forum.xda-developers.com/ =
= showthread.php?p=53448680 =
= =
= Many thanks to: =
= - [NUT] =
= - geohot =
= - MohammadAG =
= - cubeundcube =
= - nhnt11 =
= - xsacha =
= =
==============================================

* daemon not running. starting it now on port 5037 *
* daemon started successfully *
=============================================
Waiting for Device, connect USB cable now...

Make sure that you authorize the connection
if you get any message on the phone
=============================================
Device found

=============================================
Getting device variables
=============================================
Device model is D5503
Firmware is 14.6.A.0.368

=============================================
Sending files
=============================================
1 KB/s (1593 bytes in 1.000s)
4574 KB/s (657704 bytes in 0.140s)
1 KB/s (1575 bytes in 1.000s)
594 KB/s (9496 bytes in 0.015s)
13 KB/s (13672 bytes in 1.000s)

Copying kernel module...
2158 KB/s (34473 bytes in 0.015s)
0 KB/s (823 bytes in 1.000s)
850 KB/s (13592 bytes in 0.015s)
Kernel version is 3.4.0-perf-g4fd66c3
Version does not match 3.4.0-perf-ge4322cd, needs patching...
dd: conv option disabled
Kernel module patched.
error: only position independent executables (PIE) are supported.

=============================================
Loading towelzxperia
=============================================
13 KB/s (13592 bytes in 1.000s)
4117 KB/s (197320 bytes in 0.046s)
=============================================

Waiting for towelzxperia to exploit...

error: only position independent executables (PIE) are supported.
done

Checking if device is rooted...
Error: device not rooted
Premere un tasto per continuare . . .

Can you please help me?
i got this version build and kernel
Build 14.6.A.0.368
Kernel 3.4.0-perf-g4fd66c3

Thanks