function change_input_text(input) {
	var old_val = input.value;
	input.onfocus = function() {
		(this.value==old_val)?this.value = '':'';
	}
	input.onblur = function() {
		var new_val = this.value;
		(this.value && this.value != old_value)?this.value = new_val:this.value = old_val;
	}
}

window.onload = function() {
	var all_forms = document.getElementsByTagName('form');
	var forms = [];
	for(var i=0, l = all_forms.length; i<l; i++) {
		var form_can = all_forms[i];
		if(form_can.className == 'with_change') {
			forms.push(form_can);
		}
	}

	for(var i=0, l = forms.length; i<l; i++) {
		var form = forms[i];
		var inputs = form.getElementsByTagName('input');
		for(var j=0, k=inputs.length; j<k; j++) {
			var input = inputs[j];
			if(input.className != 'btn') change_input_text(input);
		}
	}
}