ORDER BY issues with UniServer

I just switched from XAMPP to uniform server today. I'm running the same scripts, without any modification.

This:

$sql = "SELECT * FROM rooms WHERE date = '$year/$month/$day' ORDER BY roomNb";

works fine. Under XAMPP it returned the room numbers ordered from 1 to X.

Under uniform server I got:

9
10
11
12
14
8
7
6
5
4
3
2
1

Any ideas?

Thanks for your time,

Alex