Ok, I admit that my hw setup is a non supported one 
(laptop with ahcpi SATA ICH7M Controller, 2x 100GB SATA local datastore, 4GB RAM, Intel Dualcore T7600 @ 2.33GHz.
But in case someone from dev might look inside the code I have recorded the offending stack trace.
This kernel panic can be reproduced every time I choose to shutdown via the VIC console.
If I go to the command line and enter halt, the system to a partial shutdown without kernel panic and ending with the line
requesting system halt. nothing more.
NOT_REACHED /build/mts/release/bora-82664/bora/vmkernel/hardware/hardware.c:620
frame=0x3a2bdb4 ip=0x62b060 cr2=0x0 cr3=0xb66d9000 cr4=0x16c
es=0xffffffff ds=0xffffffff fs=0xffffffff gs=0xffffffff
eax=0xffffffff ebx=0xffffffff ecx=0xffffffff edx=0xffffffff
ebp=0x3a2bf10 esi=0xffffffff edi=0xffffffff err=-1 eflags=0xffffffff
*0:1034/helper1-3 1:1032/helper0-1
0x3a2bf10:[0x62b060]Panic+0x17 stack: 0x82c239, 0x3a2bf2c, 0x3a2bf34
0x3a2bf20:[0x62b060]Panic+0x17 stack: 0x82c239, 0x8682dc, 0x26c
0x3a2bf34:[0x7eaf7e]Hardware_PowerOff+0x31 stack: 0xa, 0x83105e, 0x62818c
0x3a2bf5c:[0x6282c1]Init_VMKernelShutdown+0x128 stack: 0x4, 0x1, 0x0
0x3a2bf70:[0x628b39]Init_VMKernelShutdownHelper+0x30 stack: 0x4, 0xb434a, 0x0
0x3a2bfac:[0x657e83]helpFunc+0x2d2 stack: 0x1, 0x14a0088, 0x0
0x3a2bffc:[0x74e42a]CpuShed_StartWorld+0x109 stack: 0x0, 0x0, 0x0
0x3a2c000:[0x0]uhci_interrupt_info+0xfd71190f stack: 0x0, 0x0, 0x0
VMK uptime: 0:10:01:47.032 TSC: 84039065259324
0:10:01:45.537 cpu1:74427)UserLinux: 906: Powering down the system
0:10:01:47.030 cpu0:1034)VMKAcpi: 1800: Failed to prepare for power off
Starting coredump to disk using slot 1 of 1... Disk dump FAILED.
Timeout
Waiting for debugger... (world 1034)
Debugger is listening on serial port ...
Press Escape to enter local debugger
Remote debugger activated. Local debugger no longer available
