alert log stops registering entries after recluster

I have oracle version 11.2.0.2 on an oracle sun cluster OS version solaris 10.

What we did was that I manually shutdown the database, our system admin did the re-clustering which was just to add the monitor account to a resource group. The whole thing took about 10 minutes and then the system and database started up fine and all the applications are working ok too and new archive logs were generated. But one thing I noticed was that the alert log stops registering any entries after the reclustering. It stops at about the time I shutdown the database. After the reclustering, the system was brought up by the clustering scripts, but alert log does