[jadmin] no heartbeat?

[Paul C.]

On jabberd 1.4.x, what would happen if you don't have the heartbeat 
defined anywhere in the config file?  I'm trying ot fix some issues with 
our karma settings and I noticed that the heartbeat isn't defined in our 
config file.  Basically, we have two servers setup.  Server One for chat 
rooms and Server Two for the actual users.  Our Karma settings for S2S 
look like this:

    <dialback xmlns='jabber:config:dialback'>
      <legacy/>
      <ip port="5269"/>
      <karma>
        <init>50</init>
        <max>50</max>
        <inc>4</inc>
        <dec>0</dec>
        <penalty>-5</penalty>
        <restore>50</restore>
      </karma>
    </dialback>

Service IO (MIO) on both servers looks like this:
<io>
    <rate points="5" time="25"/>
</io>

Our servers provide a private services to our customers, they are not 
open to the public, so they only communicate with each other.  They are 
on their own T1, which is only open on these two ports plus SSH for 
access.  They communicate to each other on a 100mbit network. 
Basically, we are having this issue:
20051010T13:04:41: [warn] (io_select): 63.85.xxx.xxx(xx) is being 
connection rate limited
Here are my thoughts (let me know what you think!)
Is this error message the result of too strict of settings for our s2s 
Karma or is it the result of a too strict of settings on our MIO rate 
points?  If these two servers are constantly talking back and forth to 
each other, should I relax the MIO settings and allow more rate points?  
Normally, we can have anywhere from 80 to 200 connections between the 
two servers listed in netstat -a (on Solaris 9). 
We do not currently have a heartbeat listed in our Karma settings.  I 
know this can affect the end users - showing a user online when they may 
be logged off temporarily, but how does this affect Karma?  I have 
looked in the documentation and in the developers handbook, and can't 
really find much information on it.

Thanks!
Paul Cahill