I'm assuming that you're using the iSCSI Initiator --- not sure if this applies - there is a memory leak in the Windows 2003 version of the the Microsoft iSCSI Initiator versions 2.07 and 2.08 - not the actual the initiator, but the MPIO vesions 1.21. and 1.22 - see Knowledgebase article emc207833. Not sure if the MPIO version on Windows 2008 is affected by this issue, but it might be worth asking.

Also, in the iSCSI Initiator versions for Windows 2003, NIC teaming was not supported. Is it supported for Windows 2008?

glen