Do you suffer from ghost LUNs (VMFS or RDM)?
Do you suffer from unattended ESX host reboots (coredumps)?
Do you have your events log filled in with SCSI: 4510: Cannot find a path to device?
You run ESX 3.5 prior U4?
Then you may suffer EVPD pages problem and a fix is available in U4, so hurry to upgrade 🙂
More at VMware.com