Incorrect reporting of Memory Utilization for Linux Servers

I was trying out Applications Manager in trial Mode for the professional Edition, and configured it to monitor some apache servers and also some monitors of type linux to get resource information on these servers. All the servers which i was trying to monitor are RHEL AS4, and i noticed that in all of them (5 servers in count) the memory utlization is being reported incorrectly. In most cases the memory on ths system is close to 90 % utilized as per /proc/meminfo while the monitor says anywhere between 10 to 30% utilized.

I noticed that Applications Manger is using the command line "free -b" to get the memory info, and it looks like Application manager is taking the out put from the wrong line (line named as buffers/cache). I have given the out puts from two commands which probably will help you in analyzing the issue. The actual memory is utlized is 99% while the monitor is reporting it as 30%.

Output of command free (free -b)
total used free shared buffers cached
Mem: 8443310080 8424472576 18837504 0 72122368 5782761472
-/+ buffers/cache: 2569588736 5873721344
Swap: 2080366592 147456 2080219136

Output of meminfo (grep Mem /proc/meminfo)
MemTotal: 8245420 kB
MemFree: 18324 kB