It could have been created as a patch and that is far as its gotten.
Assuming that we're talking we're just talking about creating a simple .snk to create strongly named assemblies when talking about signing assembly:
I didn't see a .snk file in the Lucene.Net_2_9_4g branch when setting up the build scripts. I haven't looked in trunk yet.
The Lucene.Net_4e branch should have a already have a snk. I could add the same snk file to trunk and the 2.9.4 branch when I go add the build scripts to the trunk this weekend, so that all the branches are building strong assemblies.
Someone would still need to go back to the tag and create a 2.9.2 version using the snk whenever the next release does come out.