lcas/lcmaps they have by default debug level set to 5. Apparently it can be changed setting appropriate env variables for the globus-lcas-lcamaps interface. The variables are actually foreseen in yaim. The errors can be generated by a mistyped DN when a non-VOMS proxy is used. This is a very easy way to generate a DoS attack.
After dwngrading yaim/lcg-CE I've reconfigured the CE and it seems to be working now. I haven't seen any of the debug messages for now.