I was able to gather some more kernel information: Ther kernel obviously tries to intialise the card, but fails. Here the some grep from the kernel log:
root@gondolin:/# cat /var/log/kern.log | grep -i megasas||megaraid_sas||0b:00.0||05b
Jan 31 18:25:54 gondolin kernel: [ 1.257093] megasas: 00.00.06.12-rc1 Wed. Oct. 5 17:00:00 PDT 2011
Jan 31 18:25:54 gondolin kernel: [ 1.257103] megasas: 0x1000:0x005b:0x1000:0x9266: bus 11:slot 0:func 0
Jan 31 18:25:54 gondolin kernel: [ 1.266628] megasas: Waiting for FW to come to ready state
Jan 31 18:25:54 gondolin kernel: [ 1.266629] megasas: FW in FAULT state!!
Jan 31 18:25:54 gondolin kernel: [ 1.266631] megaraid_sas 0000:0b:00.0: megasas: FW restarted successfully from megasas_init_fw!
Jan 31 18:25:54 gondolin kernel: [ 31.183837] megasas: Waiting for FW to come to ready state
Jan 31 18:25:54 gondolin kernel: [ 31.183842] megasas: FW in FAULT state!!
I also rechecked the configuration of the RAID-Array, seems to be fine. I think the card does not like to be passed via DirectPath-I/O. Is there any alternative to this? Will I suffer a performanceloss if I just create VMFS-Partition on the RAID-volume and create a virtual harddrive that filles the whole RAID, then connect this to the VM via normal virtual SCSI adapter?