Strange load issue on NetBSD

[x25%pobox.com@localhost]

At the place where I work, I am maintaining mostly Linux servers. However, 
turns out there is 1 NetBSD (2.0, 
ouch) box that is running Apache.

Other admin reported httpd processes there turning into zombies, so I wanted to 
take a look.

I am puzzled. Average load on the machine is displayed in ranges from 3 to 10, 
yet top and all other types of 
'performance monitoring' tools (vmstat, iostat) show that machine is 99% idle. 
No processes using any CPU 
time, and no 'major' activity.

Example:

netbsd: {5} w
12:33PM  up 305 days,  1:04, 2 users, load averages: 5.53, 5.50, 5.25
USER    TTY FROM                                 LOGIN@  IDLE WHAT
username p1 x.x.x.x                             12:26PM     6 w

Box hasn't been rebooted for a while, so that is something I'll be looking at 
doing soon, but I was wondering 
if anyone has ever experienced this behaviour.

Thanks.