On occasion, identd problems are also due to the DALnet servers themselves. Sometimes, when servers are overloaded with clients, the server has problem performing the identd lookups for all the people who are trying to connect.
I'm not quite sure about the current situation, but a few weeks ago, there was also speculation that the new version of ircd may have also been related to the failed identd lookups.
Unfortunately, sometimes there's nothing much to do but to keep trying different IRC servers - sometimes, the smaller ones may work better than the bigger ones.
Oh yea, and there's
this post on the issue as well.
