I ran into an issue when working on a MOSS farm with the December update for MOSS. Before applying the update, I was running a basic x64 install with SP1. The farm with MOSS had a one-way trust to a user-based domain. The user-based domain didn’t trust the resource domain where MOSS was installed. I needed to use the syntax of stsadm -o setproperty -pn peoplepicker-searchadforsts -pv “domain:example.com,Username,Password” as the article mentioned below since I had a one-way trust.
This article also helped with the syntax.
I strongly suggest you test this in a sandbox environment before applying or attempting to do your production environment.
Hope this helps.