Encountered this issue twice so far. When failover occurs between two ASA5510's, the local IP pool for remote access users no longer works. I have to remove the pool and change the addresses to a different subnet for them to start working again, otherwise I get error 443, unable to obtain IP address for client. There is also a PtP connection to another site that is working just fine on failover, but for some odd reason the client connections suffer from this.
I have this problem too.