bb write error while sending message to bbd@hobbit2:1984?

What do these bb errors indicate?  They are happening quite often.  Are 
we running out of some resource on the host?

nmsbb at pdcads04:/var/home/nmsbb/client/logs> cat h*log
2006-08-11 22:00:03 Write error while sending message to bbd at hobbit2:1984
2006-08-11 22:00:03 Whoops ! bb failed to send message - write error
2006-08-11 22:05:06 Write error while sending message to bbd at hobbit2:1984
2006-08-11 22:05:06 Whoops ! bb failed to send message - write error