high load on exim ?

top - 09:42:28 up 95 days, 5:36, 2 users, load average: 28.23, 25.00, 27.06
Tasks: 247 total, 1 running, 245 sleeping, 1 stopped, 0 zombie
Cpu(s): 4.2% us, 2.9% sy, 0.0% ni, 0.0% id, 92.3% wa, 0.6% hi, 0.0% si
Mem: 970780k total, 190500k used, 780280k free, 832k buffers
Swap: 2096472k total, 721464k used, 1375008k free, 17908k cached

328 idbis 18 0 9752 3488 2632 D 1.0 0.4 0:00.03 /usr/sbin/exim -Mc 1F2fy4-0008WK-5S
416 idbis 18 0 8848 3732 2656 D 1.0 0.4 0:00.03 /usr/sbin/exim -Mc 1F2fyK-00005a-6r
307 root 17 0 3284 984 688 R 0.7 0.1 0:00.30 top -c
468 idbis 18 0 8344 3752 2656 D 0.7 0.4 0:00.02 /usr/sbin/exim -Mc 1F2fyl-00006h-45
36 root 15 0 0 0 0 D 0.3 0.0 8:44.50 [kswapd0]
30246 nobody 15 0 91412 11m 3296 D 0.3 1.2 0:00.69 /usr/local/apache/bin/httpd -DSSL
32606 idbis 18 0 9636 3756 2656 D 0.3 0.4 0:00.06 /usr/sbin/exim -Mc 1F2fx3-0008SU-GP
314 idbis 18 0 9532 3756 2656 D 0.3 0.4 0:00.04 /usr/sbin/exim -Mc 1F2fy1-0008W9-GY
385 idbis 18 0 8856 3756 2656 D 0.3 0.4 0:00.03 /usr/sbin/exim -Mc 1F2fyH-00005V-Nt
386 idbis 18 0 9708 3700 2656 D 0.3 0.4 0:00.03 /usr/sbin/exim -Mc 1F2fyF-00005U-Sv
387 idbis 18 0 9660 3480 2656 D 0.3 0.4 0:00.03 /usr/sbin/exim -Mc 1F2fyF-00005P-1Y
420 mailnull 17 0 9024 3828 2680 D 0.3 0.4 0:00.04 /usr/sbin/exim -Mc 1F2fyd-00006W-Tv
437 idbis 18 0 9568 3760 2656 D 0.3 0.4 0:00.02 /usr/sbin/exim -Mc 1F2fyi-00006Z-41
478 abadisvo 16 0 11868 3660 1352 S 0.3 0.4 0:00.02 webmaild - serving 203.130.255.179
1 root 16 0 2472 268 236 S 0.0 0.0 0:19.58 init [3]