system.gui.inputBox for int values?

Is there a way to make system.gui.inputBox only take int values, or do I have to use system.gui.showNumericKeypad ?

Ended up just doing this:

Days = system.gui.inputBox("Enter probation period in number of days:", "30")
try:
	Days = int(Days)
except:
	system.gui.messageBox("You must enter a number.")

Seems to work fine.