T61 hangs: AMT problem? ME System un-configuration

[nielz]

I have a Lenovo Thinkpad T61 Type 6460-66U Bios 2.26
Intel Management Engine BIOS Extension v2.5.18.0000

Recently I modified some bios settings, I think I disabled the AMT system and the Security chip, but from that moment on the system wouldn't boot. The Thinkpad logo comes up, when I press F12 the boot options come up, but when I choose one (no matter which) there is only a blinking cursor. This slightly changes when I enable AMT in the bios. Before the blinking cursor there is a message:
Firmware Version Matched ...
ME System is going through the un-configuration process
System will go through a power cycle reset upon completion

which shows for about a minute, then the blinking cursor comes up. I can get into the bios, but I can't get into the ME setup (ctrl-p doesn't do anything). I have reset the CMOS settings (by removing the battery), tried everything without pci-x cards, hdd or dvd drive but to no avail.

Below is another transcript of what happens.
___________________________

The following unsuccessful procedure was tried with default BIOS settings, with
and without Supervisor Password. Boot from CD, HD or LAN has no influence;
probably because it never reaches the stage of booting.

--Power cycle
Thinkpad logo
--2 seconds
Screen displays 3 lines:
Firmware Version Matched ...
ME System is going through the un-configuration process
System will go through a power cycle reset upon completion
--60 seconds
Blank screen with blinking underscore

--Ctrl-Alt-Del
Reboot Thinkpad logo
--F1
BIOS Setup
Config
Intel (R) AMT
Enabled -> Disabled
Save and Exit

--Reboot
Thinkpad logo
--2 seconds
Firmware Version Matched ...
ME System is going through the un-configuration process
System will go through a power cycle reset upon completion
--60 seconds
Blank screen with blinking underscore
--Forever
--Reboot
Same problem

_____________________________

Does anyone know if this is fixable in any way?

[nielz]

[slight bump after adjusting the post]