Is there a hotpatch post-6.5sp1 agent that addresses the overwriting of the
NWGINA.DLL during the agent install? REINSTALLMODE=VOMUS is not really a good
way of addressing the problem, because (for example) there might be newer files
from ZFD4.x IR6 on the machine, that should be overwritten by ZFD65 agent. We
are trying to roll out 6.5sp1 agent on top of some 4.91 clients that have a
newer NWGINA.DLL from a post-4.91 patch.

TID documenting the problem: