[Koha] Zebra size error

[Erik Lewis]

13:59:42-29/01 zebraidx(2373) [fatal] mf_write: sort55 error (4) no more space
13:59:42-29/01 zebraidx(2373) [fatal] /var/lib/koha/zebradb/biblios/register: max=4294967296 used=4294967296 available=0
13:59:42-29/01 zebraidx(2373) [fatal] Adjust the limits in your zebra.cfg

Stupid question, I'm indexing a larger load of Marc records than normal.  Looks simple enough only for one thing I don't seem to have a zebra.cfg file.  Anywhere else this setting could be hiding?  This is a 3.04 installation on Ubuntu 9.10.