question about compiling PHP and freetds 0.82

Hello all, 

I am using Freetds on a RHL ES 3 server. I installed Freetds 0.82 (/usr/local/freetds) and is works fine from the command line.

I want to use PHP to talk to an MS-SQL 2005 server. 

I currently run PHP 4.3.2. I wanted to keep that version and recompile to use mssql. Here is what I have done so far:
 

Downloaded and configured same version of php with the mssql extension. I planned to then copy the mssql.so into the existing php extension folder. 

./configure --with-mssql=/usr/local/freetds


This is the end of what results from the configure:

checking for mSQL support... no
checking for MSSQL support via FreeTDS... yes
configure: error: Directory /usr/local/freetds is not a FreeTDS installation directory

I read that it is looking for tds.h, which doesn't exist in the version 0.82 (stable release) package. It was suggested that I use an older version, which I did (0.64). I installed this from an RPM. It appears to install, but it doesn't have the tds.h and I don't know where to point the configure script. 

Other than those attempts, I can only see completely recompiling php, but I might have to modify the installed RPM of PHP and then recompile. I haven't figured out yet if that is necessary. 

Please advise. Thanks. 

Christopher Adams