Slow networkperformance in current?

A few months ago I tested my local network speed with iperf and got around
900Mbits/s. But with a newer current I get around 300Mbits/s, (using 100%
cpu usage), and to localhost: 162 Mbits/sec.

I'm running iperf -s in one terminal and iperf -c localhost on another.

FreeBSD 7.0-CURRENT #9: Mon Jul  9 13:18:23 CEST
2007     root_at_fs:/usr/obj/usr/src/sys/FS  i386

Stock kernel, but removed debuging and witness, and using SCHED_ULE.

Not knowing where to look I tried to update.
Recompiled with updated source and with SCHED_4BSD:
FreeBSD 7.0-CURRENT #9: Mon Jul  9 13:18:23 CEST
2007     root_at_fs:/usr/obj/usr/src/sys/FS  i386

Same problem, am I missing something obvious here? This does not look like
the correct numbers:
[  4] local 127.0.0.1 port 5001 connected with 127.0.0.1 port 58497
[  4]  0.0-10.5 sec    172 MBytes    137 Mbits/sec


CPU: Intel(R) Pentium(R) D CPU 2.80GHz (2856.02-MHz 686-class CPU)
  Origin = "GenuineIntel"  Id = 0xf47  Stepping = 7
  Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
  Features2=0x641d<SSE3,RSVD2,MON,DS_CPL,CNXT-ID,CX16,xTPR>
  AMD Features=0x20100000<NX,LM>
  AMD Features2=0x1<LAHF>
  Cores per package: 2
real memory  = 1072562176 (1022 MB)
avail memory = 1036025856 (988 MB)
FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs

-- 
Ståle Kristoffersen