function emailOk(emailAddr) {
		var i;
		i = emailAddr.indexOf("@");
		if (i == -1) {
				return false;
		}
		var username = emailAddr.substring(0, i);
		var domain = emailAddr.substring(i + 1, emailAddr.length)
		i = 0;
		while ((username.substring(i, i + 1) == " ") && (i < username.length)) {
				i++;
		}
		if (i > 0) {
				username = username.substring(i, username.length);
		}
		i = domain.length - 1;
		while ((domain.substring(i, i + 1) == " ") && (i >= 0)) {
				i--;
		}
		if (i < (domain.length - 1)) {
				domain = domain.substring(0, i + 1);
		}
		if ((username == "") || (domain == "")) {
				return false;
		}
		var ch;
		for (i = 0; i < username.length; i++) {
				ch = (username.substring(i, i + 1)).toLowerCase();
				if (!(((ch >= "a") && (ch <= "z")) ||
						((ch >= "0") && (ch <= "9")) ||
						(ch == "_") || (ch == "-") || (ch == "."))) {
								return false;
				}
		}

		for (i = 0; i < domain.length; i++) {
				ch = (domain.substring(i, i + 1)).toLowerCase();
				if (!(((ch >= "a") && (ch <= "z")) ||
						((ch >= "0") && (ch <= "9")) ||
						(ch == "_") || (ch == "-") || (ch == "."))) {
								return false;
				}
		}
		i = domain.indexOf(".");
		if (i == -1) {
				return false;
		}
		return true;
};

function validate(form){
	good = true;
	err = "Missing or incorrect data:\n";
	if (!emailOk(form.email.value)){
		good=false;
		err+="E-mail,\n";
	};

	if (form.username.value.length<6){
		good=false;
		err+="User Name (at least 6 characters),\n";
	};
	if (form.username.value.length>8){
		good=false;
		err+="User Name must be max 8 symbols,\n";
	};
	if (form.password.value==''){
		good=false;
		err+="Password,\n";
	};
	if (form.password.value.length < 6){
		good=false;
		err+="Password must be at least 6 symbols,\n";
	};
	if (form.password.value == form.username.value){
		good=false;
		err+="Password and Username are Too Similar,\n";
	};
	if (form.password.value.length > 8){
		good=false;
		err+="Password must be max 8 symbols,\n";

	};

	us_pass = true;

		for (i = 0; i < form.username.value.length; i++) {

				ch = (form.username.value.substring(i, i + 1)).toLowerCase();

				if (!(((ch >= "a") && (ch <= "z")) ||

						((ch >= "0") && (ch <= "9")) ||

						(ch == "_") || (ch == "-") || (ch == "."))) {

								us_pass = false;

								good = false;

				}

		}

		if (! us_pass) err+="Username may contain only symbols from a-z, A-Z, 0-9,\n";

	us_pass = true;

		for (i = 0; i < form.password.value.length; i++) {

				ch = (form.password.value.substring(i, i + 1)).toLowerCase();

				if (!(((ch >= "a") && (ch <= "z")) ||

						((ch >= "0") && (ch <= "9")) ||

						(ch == "_") || (ch == "-") || (ch == "."))) {

								us_pass = false;

								good = false;

				}

		}

		if (! us_pass) err+="Password may contain only symbols from a-z, A-Z, 0-9,\n";

	err+="please correct and fill the data and click Join button again.";

	if (!good) {

		alert(err);

	};

	return good;
}