FreeBSD 8.0 how to enter kernel debugger inside vmware

[Daniel Mueller]

Hi all

I have an unstable machine running FreeBSD 8.0-RELEASE inside vmware. It
freezes on average once a week but doesn't panic, so i would like to
enter the kernel debugger, to at least being able to force a panic.
Unfortunately, i have no serial interface and can't enter into the
debugger on the console using ctrl-alt-esc either, because it conflicts
with the key sequence to leave the console in the vmware client. What
can i do?

many thanks and best regards
-Daniel