I think buildmeister is a user name. I think buildmeister is also a user group name.
I guess it used internally by rpm.
I install driver as root in text mode not in XFree86
I think the error is :
>Bad exit status for /var/tmp......
but not buildmeister.
The message before error message is your hint.
I haven't try make NVIDIA_kernel.tar.gz
Sorry about that.