VS2010 won't show TFS2010 build log

I've noticed that some of my tfs2010 builds won't display a link to a build log on vs2010 build details page. All the builds (those that do show the log appropriately and those that 开发者_如何学Pythondon't) run the same xaml build template but different .proj msbuild scripts. All the builds use MSBuild.ExtensionPack and MSBuild.Community.Tasks as well as a couple of my own custom tasks.

How can I get my vs2010 build logs back? Or at least how am I supposed to troubleshoot the issue?

Seems that the problem only manifests itself if there are multiple targets (besides InitialTargets) in the .proj file and one is explicitly selected (in the build definition properties) with the /t: msbuild argument.