no default graphs are displayed

[case]

I have set up Cacti 0.6.8a on Redhat 7.2, with mysql 3.23.49, php-4.1.2, and rrdtool 1.0.39.
I have checked my permissions on the files and things seem to check out.
The logs do not give an indication why the default graphs are not rendering. I am getting data updated into the rrd files. My rrd.log is showing the graph sources. Below is a sample from rra/rrd.log:

10/30/2002 1:14 PM - CMD: /home/rrdtool/src/rrdtool graph - \
--imgformat=PNG \
--start="-2678400" \
--title="Load Average" \
--rigid \
--base=1000 \
--height=150 \
--width=500 \
--alt-autoscale-max \
--units-exponent=1 \
--vertical-label="Average Load" \
DEF:a="/var/www/html/cacti/rra/system_loadavg.rrd":1min:AVERAGE \
DEF:b="/var/www/html/cacti/rra/system_loadavg.rrd":10min:AVERAGE \
DEF:c="/var/www/html/cacti/rra/system_loadavg.rrd":5min:AVERAGE \
CDEF:cdefb=a,b,c,+,+,3,/ \
CDEF:cdefc=a,b,c,+,+,3,/ \
CDEF:cdefd=a,b,c,+,+ \
AREA:b#EACC00:"10 Minute\: 0.09\n" \
STACK:cdefb#EA8F00:"5 Minute\: 0.11\n" \
STACK:cdefc#FF0000:"1 Minute\: 0.31\n" \
LINE1:cdefd#000000:"Total"

Thanks - case

[case]

I went ahead and added the export directory in cacti and all of the graphs that have data associated with the graphs are placed into the directory fine. I do not understand why the graphs are showing up as broken links in the cacti interface.