ejabberd-2.1.0_rc1 crash with 2 mln users

Hello,

I wrote a test that generated 2 mln users for ejabberd-2.1.0_rc1, after restart the node crashed with the following message: "eheap_alloc: Cannot allocate 583848200 bytes of memory (of type "heap")." The test had been made on one machine (not in a cluster).

Environment :
Ubuntu 9.04, kernel : 2.6.28-11-generic
1G RAM
AMD Athlon, 2.1GHz
ejabberd-2.1.0_rc1
erlang-r13b01

both erlang and ejabberd are compiled from source code

If you need more details, ask me

Any help will be greatly appreciated