Are you sure that the SFP-GIG-LX are working, what about the fiber optic cable did you check it, on the other end did you check (gbic & media converter)?
Vlan 21 is the VOICE, right? Try this, in my example vlan 26 is the voice vlan 6224_UBF# sh run interface range ethernet e(15-16) switchport mode general exit interface ethernet g2 switchport mode trunk exit vlan database vlan 26 exit interface ethernet e23 switchport access vlan 26 exit interface r...