Good morning,
I`ve seen that issue on all of my clients´ XP SP3 machines (fully patched), too, during a local slipstreamed installation of office 2007 sbs with sp2 from CD. My first thought was that this issue was associated to my slipstream cd, but now I read that post!
We have SEP MR4 MP2 installed in that infrastructure and I disabeld Auto-Protect and Tamper Protection during installation.
There was no high CPU or Memory Usage during the process, but I realized that it takes fewer time (3/4 h) on the slowest and oldest workstion than on the newest, fastest one (3,5h).
regards,
Rolf