reconnect esxi4.1 FC host to CX4 target

We're having a setup  with a couple of ESXi4.1 hosts connected to a CX4 running flare 30 in ALUA mode 4, hosts running in ALUA_SATP_CX in Round-Robin mode.

During a disk failure last weekend all hosts lost one active path to SPA1, backup path via SPB0 was still up and running over same HBA.

We tried to do a reconnect from the CX4 host properties but that didn't reconnect the FC initiator.

We removed zoning for this path, re-applied the zoning and ESXi host logged in again to SPA1.

Two questions:

How can I loose a path when array starts to rebuild a drive, never seen that one before.

Is there a way to force the ESXi host to re-login to the FC target without the zoneing trick.

Regards,

John