[f-nsp] Confusing display for STP status

[Gabriel Barazer]

Hello,

I am a bit confused about where STP is enabled or not on my Foundry 
BigIron : by default STP is disabled on this switch, but the way it is 
displayed is very strange :

I have 7 VLANs, with no STP options (so STP is disabled as this is the 
default)

- show vlan confirm this by displaying "Spanning tree Off" on all these 
vlans

- show span also confirm this : "Spanning-tree is not configured on 
port-vlan 1" and so on for other vlans

BUT show interface says "STP configured to ON" on all my interfaces. Why 
are the interfaces STP enabled, whereas vlans have STP _disabled_ ?

I can manually disable STP on each interface by setting "no span" but 
why is this necessary on a layer 3 switch like the BigIron where it is 
mentionned in the manual that STP is NOT enabled by default ?

Any help appreciated,

Regards,

Gabriel