number of child processes

[List]

Hi List,
I had just upgraded from 2.64 to 3.0. The first thing i notice is that there 
are spamd child processes. I have 5 in total.

root      5691  0.0  1.3 30536 13604 ?       S    Sep29   0:28 spamd child
root      5802  0.0  1.7 30260 17764 ?       S    Sep29   0:29 spamd child
root      5887  0.0  1.1 29632 11592 ?       S    Sep29   0:29 spamd child
root      5925  0.0  1.5 29764 16144 ?       S    Sep29   0:27 spamd child
root      6155  0.0  1.7 30564 18176 ?       S    Sep29   0:30 spamd child
This is normal?
best regards