how to detect second proc on amd64x2 ?

[rmkml]

Hi,
sorry for stupid question,
but I have installed freebsd amd64 port
boot UP (uniproc) ok
compiled SMP kernel
reboot :
FreeBSD 6.1-RELEASE #0: Sun Jun 25 12:25:35 UTC 2006
     root at freebsd61x2.test.com:/usr/src/sys/amd64/compile/SMP
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: AMD Athlon(tm) 64 X2 Dual Core Processor 3800+ (1989.82-MHz K8-class CPU)
...
but not detect two proc (dmesg and top),
why ?
maybe acpi error ? :
     ACPI-0159: *** Error: AcpiLoadTables: Could not get RSDP, AE_NO_ACPI_TABLES
     ACPI-0213: *** Error: AcpiLoadTables: Could not load tables: AE_NO_ACPI_TABLES
ACPI: table load failed: AE_NO_ACPI_TABLES

thx for any help
Best Regards
Rmkml