USB Panick and Card Reader help needed, please

Hello,

I'm stuck here, I cannto PXEboot my soekris and my card reader doesn't 
work.
So far I played with sys/dev/usb/umass.c and sys/cam/scsi/scsi_da.c quirks, 
but nothing helped. How can I verify that my patches are used with my 
device? What strings do I have to define in scsi_da.c?
Here some info:
umass0: Generic USB Storage Device, rev 1.10/1.00, addr 8

port 3 addr 8: full speed, power 100 mA, config 1, USB Storage 
Device(0x5010), Generic(0x07c4), rev 1.00

scbus3 on umass-sim0 bus 0:
<Generic USB Storage-SMC 0180>     at scbus3 target 0 lun 0 (da0,pass2)
<Generic USB Storage-CFC 0180>     at scbus3 target 0 lun 1 (da1,pass3)
<Generic USB Storage-MMC 0180>     at scbus3 target 0 lun 2 (da2,pass4)
<Generic USB Storage-MSC 0180>     at scbus3 target 0 lun 3 (da3,pass5)

When I plug it in, the reader gets accessed every 2 seconds or so for 
several minutes. During that time I cannot mount anything else! After all 
these errors I can access the device, but very slowly and umounting it 
takes onther view minutes!
Please find attached a panic with trace I got and the logs of the reader 
behaviour. Interesting is, when I unplug it before these errors run into 
any timeout, I see "Synchronize cache failed, status == 0x39, scsi status 
== 0x0" so I had bet it can be made working by devining a scsi_de.c quirk. 
But no luck, perhaps I took the wrong string?
Here's waht I tried:
umass.c:
	{ 0x07c4, 0x5010, RID_WILDCARD,
	  UMASS_PROTO_SCSI | UMASS_PROTO_BBB,
	  FORCE_SHORT_INQUIRY | NO_START_STOP | IGNORE_RESIDUE
	}
I tried all kinds of quirks!

scsi_da.c:
{	/*
	* Datafab MotionFlash CS4-USBN50 6in1 card reader.
	*/
	{T_DIRECT, SIP_MEDIA_REMOVABLE, "Generic*" , "USB Storage*", "*"},
	/*quirks*/ DA_Q_NO_SYNC_CACHE
},

I'm no developer so I don't know how to get this thingie working. But I'm 
quiet sure it has been working with FreeBSD arround 5.2 times. Needless to 
say that it's working with other OS's.

Thnaks in advance,

-Harry

P.S.: I'm only subscribed to current_at_