It seems as though the emulex scsi-esdi adapter has some problems when
another device is being utilised at the samt time. The disk and 
controller is the one in the sun shoebox, mounted together with a tape 
drive. It is found as:

esp0 targ 0 lun 0: <EMULEX, MD21/S2 ESDI, A00> SCSI0 0/direct fixed
sd0 at scsibus0: 312MB, 1224 cyl, 15 head, 34 sec, 512 bytes/sec

When another device is active at the same time as the disk conected to the
esdi-adapter I get the following: 
sd3(esp0:1:0): esp0: timed out [ecb 0xf85d8898 (flags 0x3, dleft 2a00, stat 0)],
 <state 3, nexus f85d88f0, phase(c 100, p 101), resid 2000, msg(q 0,o 0) >
sd0(esp0:0:0): esp0: timed out [ecb 0xf85d88f0 (flags 0x0, dleft 2000, stat 0)],
 <state 3, nexus f85d88f0, phase(c 100, p 101), resid 2000, msg(q 0,o 0) >

Since the drive is recognized as "scsi0" I assume it is not compliant 
with modern standards (scsi-2 etc). Is anyone using this type of 
hardware? Is any of the quirk entries a good idea to try?

Peter