how do I preset ddb's LINES to zero

Hi,

I've the stock 10.0 boot.iso booting within a KVM based test
framework.  I'd like to set things up so that should there be a panic,
it dumps registers et.al., without stopping half way waiting for
someone to hit the space bar vis:

r9          ffffaf80b451d080
r10         8000000001d9a063
r11         0
r12         0
--db_more--

Is there a way to stop this without having to rebuild the kernel.

Andrew