[dotSILENT]

That's really weird, I just tested it on both linux & windows, vehicles created with both CreateVehicle and AddStaticVehicle worked fine.
The current value shown (0.0) is not valid, and it appears like the plugin couldn't initialize properly and didn't call

Code:

HandlingDefault::Initialize()

Check your logs, are there any errors? The plugin needs to hook a few things in the server in order to work properly, it's possible that other plugins like YSF or SampAC are affecting this. Although I just checked with YSF and there's no problem with loading it either before or after chandlingsvr.
What's your plugins line in server.cfg? Are you running the server on linux or windows? What version of the server are you running? Are other vehicles, or attributes in the same vehicle working fine?

This definitely looks like some initialization problem.

Edit: however if IsPlayerUsingCHandling() returns true, then the RakNet hook must be working, so that'd mean the initialization was successful, which makes it even more weird.