"rtc: lost some interrupts at 1024Hz." Messages after Installation of Zaptel

I got a lot of "rtc: lost some interrupts at 1024Hz." messages after installed zaptel-1.4.5.1 and the ztdummy module was enabled. It seems that the RTC periodic_IRQ can not be enabled.

"cat /proc/driver/rtc" shows:
rtc_time : 02:55:42
rtc_date : 2007-10-06
rtc_epoch : 1900
alarm : 00:26:49
DST_enable : no
BCD : yes
24hr : yes
square_wave : no
alarm_IRQ : no
update_IRQ : no
periodic_IRQ : no <= this should be yes for a normal system
periodic_freq : 1024
batt_status : okay

The Linux is Debian GNU/Linux 4.0r1 and kernel version is 2.6.18-5-686.

The problem seems to be related to ACPI (Advanced Configuration and Power Interface). Finally, I fix this by turning off ACPI and using the older APM (Advanced Power Management) for power off control.

Disable ACPI:
Edit "/boot/grub/menu.lst" and add "acpi=off" in kernel boot statement.

title Debian GNU/Linux, kernel 2.6.18-5-686
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-5-686 root=/dev/sda1 ro acpi=off
initrd /boot/initrd.img-2.6.18-5-686
savedefault

Enable APM for power off control:
Add "apm power_off=1" to the end of "/etc/modules".