Multiple validations on an input

I want to do multiple validations on an input, but cannot figure out how or if it is possible. I created my own validate.maxValue function and it works alone, but not with another.

type : 'text',
id : 'width',
label : editor.lang.common.width,
'default' : 661,
validate : [CKEDITOR.dialog.validate.notEmpty( lang.widthRequired ),
            CKEDITOR.dialog.validate.maxValue( 662, lang.maxWidth )],
commit : commitValue,
setup : loadValue

I tried it like this, also enclosed in { }, [ ], or even declaring the validate parameter twice.
Am I going about it wrong? or is it not possible?