Inconsistent results in special characters with Apache/PHP/FreeTDS, but not with PHP/FreeTDS from command line
Frankly i have no idea what makes such kind of inconsistent work. but i would like to advice you to change FreeTDS & unixODBC to stable releases. since FreeTDS lack of documentation & support. i am using v0.82 for along time. and it works fine.
https://gitorious.org/freetds/mars-freetds/source/52e59affc0110c5ddd379ef1e45c4554123f27b5:README#L2
Another way to look for problem detailed is using PDO MsSQL in testfs1.php. by this way you can address the problem better if native mssql extension has any effect on this inconsistency.