X and OpenOffice.org lockups with Jack limits.conf changes

[Keith Sharp]

Hello,

I have downloaded Jack from Extras (for FC5) and made the changes
to /etc/security/limits.conf as described in the README.fedora file.  

kms - rtprio 20
kms - memlock 256000

(I am not confident that I have chosen the correct value for memlock, I
have 1Gb RAM in this system).

All was good and my music making was progressing well until I ran
OpenOffice.org to update a spreadsheet.  Repeatedly my entire display
would lockup requiring a login over the network and the killing of X (or
dropping to runlevel 3 and then back to 5).  Reversing the changes to
limits.conf allowed me to login and run OpenOffice.org without any
problems.

Hardware is a ATI Technologies Inc RV370 [Radeon X300SE] running only
standard FC5 Radeon X drivers (xorg-x11-drv-ati-6.5.8.0-1) and kernel
2.6.17-1.2157_FC5smp.

Has anyone else seen this?  Any suggestions for debugging?

Thanks,

Keith.