Memory Usage at 70%

Greetings Experts,

I have an HP Proliant DL360 G4 that currently has 1G of memory. The OS is server 2003. My performance monitoring application is sending me notices that memory is at or above 70%. I would like to add additional memory as the server will accomodate 12G but our IT "experts" are saying that it really does not need any additional memory and that 70% is actually good. I understand that high memory utilization on a database is optimum but not sure if that's true for an application server. What are your thoughts on this.

Thanks,
Brian