Create /etc/iscsi/iscsid.conf, bold are changes made according to the Dell site, italic is changes made by me. The remainder are the default values as supplied by CentOS 5.5:

node.startup = automatic
# node.session.timeo.replacement_timeout = 120
node.session.timeo.replacement_timeout = 144
node.conn[0].timeo.login_timeout = 15
node.conn[0].timeo.logout_timeout = 15
# node.conn[0].timeo.noop_out_interval = 5
node.conn[0].timeo.noop_out_interval = 10
# node.conn[0].timeo.noop_out_timeout = 5
node.conn[0].timeo.noop_out_timeout = 15
node.session.err_timeo.abort_timeout = 15
node.session.err_timeo.lu_reset_timeout = 20
#node.session.initial_login_retry_max = 8
node.session.initial_login_retry_max = 4
node.session.cmds_max = 128
node.session.queue_depth = 32
node.session.iscsi.InitialR2T = No
node.session.iscsi.ImmediateData = Yes
node.session.iscsi.FirstBurstLength = 262144
node.session.iscsi.MaxBurstLength = 16776192
# node.conn[0].iscsi.MaxRecvDataSegmentLength = 262144
node.conn[0].iscsi.MaxRecvDataSegmentLength = 65535
discovery.sendtargets.iscsi.MaxRecvDataSegmentLength = 32768
node.conn[0].iscsi.HeaderDigest = None
# This line did not exits
node.conn[0].iscsi.DataDigest = None
node.session.iscsi.FastAbort = Yes