700kb of RAM per connection

Hello,

I tried to connect 600 idle users (just connect and authenticate) to
my ejabberd instance and found out that the process eats 400 mb of RAM
+ virtual.
For 300 users it takes about 210 mb. For 0 users online ejabberd takes < 30 mb.

What could be the reason for such a behavior?

I tried erlang & ejabberd versions from Ubuntu 8.10 repository and
also tried latest erlang (R12B-5) and ejabberd (2.0.3) from source.
All the same.

Thanks.