i get about 25mh/s on my dual QX9775's at 3.2 (8 threads)
FreeBSD/SMP: Multiprocessor System Detected: 16 CPUs
cpu0 (BSP): APIC ID: 0
cpu1 (AP): APIC ID: 1
cpu2 (AP): APIC ID: 2
cpu3 (AP): APIC ID: 3
cpu4 (AP): APIC ID: 4
cpu5 (AP): APIC ID: 5
cpu6 (AP): APIC ID: 6
cpu7 (AP): APIC ID: 7
cpu8 (AP): APIC ID: 16
cpu9 (AP): APIC ID: 17
cpu10 (AP): APIC ID: 18
cpu11 (AP): APIC ID: 19
cpu12 (AP): APIC ID: 20
cpu13 (AP): APIC ID: 21
cpu14 (AP): APIC ID: 22
cpu15 (AP): APIC ID: 23
[2011-08-18 10:17:38] 16 miner threads started, using SHA256 'c' algorithm.
Don't know if I got it wrong
And I just tried to throw -t 16 to it, doesn't change anything
Are you using Jgarzik + FreeBSD also?