[CentOS] HDD usage oddity

Hi,

	2 of my Centos4 servers are showing weird behavior.

[root at server1 ~]# du -sh /var/
1.8G    /var/
[root at server1 ~]# df -h /var
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda7             4.3G  3.9G  181M  96% /var

[root at server2 var]# df -h /var
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda7             2.9G  2.7G     0 100% /var
[root at server2 var]# du -sh /var/
1.6G    /var/

du seems to be reporting the right size

Anyone seeing this?