mysql version 4.0.13 on linux red-hat 9
mysql> select version();
+-----------+
| version() |
+-----------+
| 4.0.13 |
+-----------+
1 row in set (0.00 sec)

mysql> select @a:=itemid from sellitem where itemid = 9;select @b:=itemid from sellitem where itemid = 11;select @a > @b;
+------------+
| @a:=itemid |
+------------+
| 9 |
+------------+
1 row in set (0.00 sec)

+------------+
| @b:=itemid |
+------------+
| 11 |
+------------+
1 row in set (0.00 sec)

+---------+
| @a > @b |
+---------+
| 1 |
+---------+
1 row in set (0.00 sec)

mysql>

mysql version 4.0.16 on win2k
mysql> select version();
+------------------+
| version() |
+------------------+
| 4.0.16-max-debug |
+------------------+
1 row in set (0.01 sec)

mysql> select @a:=itemid from sellitem where itemid = 9;select @b:=itemid from s
ellitem where itemid = 11;select @a > @b;
+------------+
| @a:=itemid |
+------------+
| 9 |
+------------+
1 row in set (0.00 sec)

+------------+
| @b:=itemid |
+------------+
| 11 |
+------------+
1 row in set (0.00 sec)

+---------+
| @a > @b |
+---------+
| 0 |
+---------+
1 row in set (0.00 sec)

mysql>

any idea ?