function str_ireplace( f_needle, f_replace, f_haystack ){	// Case-insensitive version of str_replace().
	// 
	// +	 original by: Martijn Wieringa
	var result = '';
	var index = 0;
	var haystack = f_haystack.toLowerCase();
	var needle = f_needle.toLowerCase();
	while((index = haystack.indexOf(needle)) > -1){
		result += f_haystack.substring(0, index);
		result += f_replace;
		haystack = haystack.substring(index + f_needle.length);
		f_haystack = f_haystack.substring(index + f_needle.length);
	}
	return result + f_haystack;
}

str_ireplace('l', 'l', 'HeLLo');