HELP - backups suddenly extremely slow on Domino client

Knowing that this list gets must faster response than logging a problem
with Tivoli support, I thought I would ask for suggestions here first.
Here are version levels:
Client: - Windows 2000 running: - TSM client Version 5.1.1
                        - Domino TDP  Version 1.1 (1.1.1.01)
                                                            - Domino Server
Level - 5.0
                        - Domino Server build  - 166
                        - Domino Server Logging - No logging
Server: - Z/800 running: - OS/390 2.10
                                            - TSM Server Version 4.2.2.0
Last weekend we upgraded our Server from a 9672 to a Z/800 and moved our
storage from 3990's to a Shark.  This upgrade included a change from an
ethernet to Gigabit ethernet connection to our enterprise server.  Our
backups for most of our machines that are in this building now run very
much faster, as would be expected by going to gigabit ethernet.  The only
exception is this  one Domino server.  Any TSM backup for this client now
runs extremely slow.  All transfer rates are much slower.  For example,
previous rates of 150-200 KB/sec are now 20-30 KB/sec.  However I tried an
FTP from this client and it has a very high transfer rate.  One thing I did
notice in looking at the TSM domino TDP client logs is that each of the
three times that the backup has started since this problem has been
occurring, the backup finished backing up some files (twice for only a few
minutes, once for almost a half hour), and then it would generate a message
about starting the backup of a database and then the next message would not
be seen for hours later.  In one case this was nine hours later!  This is
not always the same database.  The first two times it was domlog.nsf.  For
last night's run (which is still running), we excluded that database and
this time the long wait was after the start of
Quickplace\catlv-mh\PageLibrary85256CBC004E54B.nsf. (Note, other
PageLibrary nsf files do not get hung up this long.) When things get moving
along again, the domino TDP client log still shows the transfer rates of
the files as being very very low.  We re-booted this Windows machine last
night before the start of the backup.  I'm at a loss as to why this could
be happening and I'm am scheduled to be on vacation for 10 days after
today.  Any help would be appreciated.