When attempting to enable the extension php_ldap.dll from the 4.3.0 windows binary build I first copied the dll to c:\php\, set the proper variable in php.ini to tell php to look for extensions in c:\php and uncommented the line extension=php_ldap.dll.  save, shutdown iis, restart to get an error telling me that module c:\php\php_ldap.dll is not found and there is a refrence to function Unknown().  

After verifying that I did not screw up my copy job and the file c:\php\php_ldap.dll DID exist I came back to the site and did a serch for others having the same problem.  In 2001 there were many refrences to the same error and the solution was to move libsasl.dll to the same location as php_ldap.dll.  I also found documentation stating that libsasl.dll was already bundled into 4.3.0.  I was unable to locate libsasl.dll anywhere in the binary zip of 4.3.0.

I've noticed at least two other people here experiencing similiar problems.