Error in MySQL SELECT UNION Statment

I have the following script on a page:

include("database_connection.php");
$stmt = "(SELECT * FROM tbl_a WHERE field_b != 'Other' ORDER BY field_b)";
$stmt .= " UNION (SELECT * FROM tbl_a WHERE field_b = 'Other')";
$rs = mysql_query($stmt) or die (mysql_error());

I have Apache/MySQL/PHP on two computers; each has the same versions. I can't figure out why this script works on one but the other says, "You have an error in your SQL syntax near '(SELECT * FROM tbl_a WHERE field_b != 'Other' ORDER BY field_b' at line 1"

I know I have an active database connection because I can get other pages to show data properly. I know the data is there because first, I dumped from the working computer, and second, I checked through MySQL monitor.

Anyone know what I'm doing wrong with my SQL statement?

Errrr...

I am very sorry!! No need to respond - I found my problem; it was actually two-fold.

First, I am an idiot.
Second, I have MySQL 4.0.12 at home, but had 3.23 at the office where I was having trouble. Simple upgrade fixed that.

Again, I'm sorry.