hammer-mount: malloc limit exceeded panic

[Michael Neumann]

I got this panic 3 times today with 2.0, when building packages like 
firefox3 on a hammer partition.

  hammer-mount: malloc limit exceeded
  hammer_alloc_mem_record+0x22
  hammer_ip_add_directory+0x1d
  hammer_vop_ncreate+0xba
  vop_ncreate+0x3d
  vn_open+0xf3
  kern_open+0x84
Strange, as I have 3GB of memory. Is there a memory leak somewhere?
I just build 1 or 2 packages (distfiles are already fetched), no other
activity. And it's a UP machine.
Regards,

  Michael