IP SOURCE GUARD?

[csco11224163]

hi everyone , I got a problem that I need to config a secure feture ,IP SOURECE GUARD ,in switch 2960 with ios is "universalk9-mz.122-53.SE2".My topology is :

(65 sw)___l3-link____(3560-sw)_____trunk_____(2960-sw).

The configration of the 3560 is :
ip dhcp snooping vlan 22,33,44
information option allow-untrusted
ip dhcp snooping

and the configration of the 2960 is:
ip dhcp snooping vlan 22,33,44
ip dhcp snooping

interface g0/1(up link)
ip dhcp snooping trust

I found someone in vlan 22 can access the gateway,and someone in the same vlan can't access the gateway.so I don't know why it is?

[csco11224163]

and the dhcp server link to the core switch, but it is a win-server do not support option 82.And I can not config : ip veryfy source.