Seems you are asking about two different things here so we should clarify on each one. First on the vlan managment interface which is what was discussed in the first reply. You can have multiple of these but only one active. This is just a vlan interface created in config mode for managment of the switch. There is no routing here. This is just like assigning an IP address to a PC if you want to think of it like that. There is no where for subinterfaces on this switch that is normally done on the router interfaces for routing between vlans.
Second on the vlans themselves you can have all the vlans you want, well at least up to the limit of what the switch will hold which is 64 or maybe higher just check the release notes. To do this go into the vlan database and create the vlans as needed. Next go into the interface config and assign a vlan to the interface using the switchport command. This is a layer 2 interface and assigns that port to the vlan. As for using the "multivlan" we do not recommend this as the was a precursor to using trunking on the switch which is the recommended method today.
