Description:
------------
When I configure with freetds for mssql configure fails 
with the following warning:

configure: error: Could not find /usr/local/lib/
libtds.a|so

But the file libtds.a exists at /usr/local/lib/libtds.a. 
The identical configure worked for 5.0.0

/usr/local/lib] jonb% ls
libct.2.0.0.dylib       libpng.dylib            
libtds.dylib            libxml2.2.6.6.dylib
libct.2.dylib           libpng12.0.1.2.5.dylib  
libtds.la               libxml2.2.dylib
libct.a                 libpng12.0.dylib        
libtdsodbc.0.0.0.dylib  libxml2.a
libct.dylib             libpng12.a              
libtdsodbc.0.dylib      libxml2.dylib
libct.la                libpng12.dylib          
libtdsodbc.a            libxml2.la
libexslt.0.8.0.dylib    libsybdb.4.0.0.dylib    
libtdsodbc.dylib        libxslt.1.1.0.dylib
libexslt.0.dylib        libsybdb.4.dylib        
libtdsodbc.la           libxslt.1.dylib
libexslt.a              libsybdb.a              
libtdssrv.1.0.0.dylib   libxslt.a
libexslt.dylib          libsybdb.dylib          
libtdssrv.1.dylib       libxslt.dylib
libexslt.la             libsybdb.la             
libtdssrv.a             libxslt.la
libpng.3.1.2.5.dylib    libtds.3.0.0.dylib      
libtdssrv.dylib         pkgconfig
libpng.3.dylib          libtds.3.dylib          
libtdssrv.la            xml2Conf.sh
libpng.a                libtds.a                
libxml2.2.5.11.dylib    xsltConf.sh


I checked the file ext/mssql/config.m4 spelling and it 
seems correct but it is not recognizing the file name 
for some reason.

Without the mssql extension it compiles fine.

By the way, you need a drop-down option for 5.0.3RC1 on 
the form.

Reproduce code:
---------------

 '--with-mssql=/usr/local'

Actual result:
--------------
configure fails