The post I found said they fixed their problem but never elaborated on HOW they fixed it.
There may well be a workaround in the LPC code, but I assumed you were aiming for the driver to be a drop-in replacement for the older C version.
For my test case, I unpacked the discworld lib, compiled the driver from my own git repository (version 2.27.2), and verified that it worked, connected to I3, and I could walk around and do a few basic things. Then I compiled the newer C++ version of the driver using the same local_options files and booted the same mudlib, in place, with that newer driver. The result is that it boots, connects to I3, but logging in results in "Command Queued" no matter what you type.
Since the mudlib code has not changed, and the configuration has not changed, this must be a change in the driver's code, somewhere. Since it has to do with delays, my initial guess is that it might be related to the posix timer stuff, but that's just a guess.