I have checked in NX 10 by building a simple Part file with a pavement shape.
The Units used is the Millimeters in the New dialogbox.
Then I exported into .VRML file format by using the menu File > Export > VRML.
A VRML file is in text format, so, we can open it in a text editor as Notepad++.
I didn't find a line who refers to millimeter or the unit used.
So we can conclude that the 3D standard unit used.
I mean, an unit who don't refers to millimeters, meters or imperial units.
For example, in NX, the one 3D unit is egal to one millimeter.
So, the pavement has a size of 125 units who it means 125 mm.
When exporting to .vrml format, the cube still has a size of 125 units.
But it doesn't refer to millimeters.
When importing in Creo View or in Creo Illustrate, one 3D unit egal to 1 meter.
So the 3D doesn't have the same unit between NX and Creo View or Creo Illustrate.
In Creo View when using in the Markup tab, the Envelope tool, we can check that :
So, I guess the solution might be to export in step or iges file format instead.
It is a common used in industrial business to exchange data and take care of the real unit.
I am not able to check that in my workstation because step export doesn't work in NX.