Temporary long delay (Qmail and Real -Time )

[Kornyakov Yevgeniy]

I have strange delay --
If clients (or other servers) d't use my
SMTP server during 10 (or more) minutes
appear timaut about 1 min.
After this timeout all working OK - without
some timeout till next pause from work SMTP server...
I use tcpserver with -R -H options and Slackware linux...
I suspect this problem have to do with reduce process prioritet
and remove all qmail daemons to swap...
How I can avoid this  ???