This is associated with another thread, but am reposting to make sure all see new development as it seems crucial to me. So, apologies for the double posting.
Well I think I figured out the problem (with some help.) My router whose ARP cache the switch port mapper queries sits outside my firewall (which I assume most of yours do also?) So, that router's ARP cache associates all IP addresses with the M.A.C. of the firewall not of the devices themselves, so when Switch port mapper maps IPs to M.A.C.s it maps them all to that one M.A.C. which is on one port of one switch. How do I get around this??
What version of Switch Port Mapper are you running? The older versions only used one VLAN when it performed its search. The 7.0 version of SPM is able to span all VLAN's. I think you may be spannig only VLAN1. Hope this helps.
If you have maintenance, you can download the pre-release of 7.0.