Yes it is possible, either by configuring it for digital input which allows you to select (I think) 8 different speeds or by using the anologue speed control input and mach's PWM output which may require smoothing. I'm sure you'll find it if you look on CNC zone. I've not done it yet as I prefer to control it myself.

Here's the English-ish manual which should clarify things:

http://www.jinlantrade.com/ebay/invertermanual.pdf