/var Full ?

[GRF .]

   I am running FBSD 5.2.1 and my /var partition is giving me cannot write 
to disk errors, disk is full.  I cleared out what I could and got it down to 
about 98% but I have some strange findings which I will show below.
[/var]> df -h
Filesystem    Size   Used  Avail Capacity  Mounted on
/dev/ad0s1a   248M    55M   173M    24%    /
devfs         1.0K   1.0K     0B   100%    /dev
/dev/ad0s1e   248M    38K   228M     0%    /tmp
/dev/ad0s1f    70G    53G    11G    83%    /usr
/dev/ad0s1d   248M   223M   4.5M    98%    /var

#cd /var
# du -hd1
2.0K    ./account
6.0K    ./at
16K    ./backups
4.0K    ./crash
390K    ./cron
5.8M    ./db
2.0K    ./empty
2.0K    ./heimdal
508K    ./log
1.9M    ./mail
4.0K    ./msgs
2.0K    ./preserve
40K    ./run
2.0K    ./rwho
66K    ./spool
1.3M    ./tmp
20K    ./yp
2.0K    ./games
1.0M    ./ftp
394K    ./usermin
2.0K    ./.snap
11M    .

Now how can /var be 11Meg and also fill up 98% or 223 Meg at the same time?  
What is eating up my partition space?  Uptime is 149 days and I suppose I'm 
due for a reboot but I have others with processes going on the box and I 
hate to reboot.