It sounds like the A record for the server in question has both
addresses associated with it? If so, then DNS "round-robins" its
replies, handing out one address, then the other, etc. for each request
for the record. The reason workstations seem to be "stuck" on one or
the other is they've probably cached the initial reply they received,
and instead of asking for new resolution with each request, they just
reuse the cached info.
bd
NSC Volunteer SysOp
www.InsightNetSolutions.net