|This Console variable has been removed from the game.
This cvar is also known as Smooth Mouse and fixes issues where mouse reaction time is very delayed. It also requires that gxCursor (also known as Hardware Cursor) is enabled as well.
To enable this cvar:
/console gxCursor 1 /console gxFixLag 1
The first line enables Hardware Cursor, the 2nd line enables Smooth Mouse.