php_oci8.dll: Invalid library (maybe not a PHP library)

I see I'm not the first fighting against the following php_oci8.dll problem: Invalid library (maybe not a PHP library) 'C:\php4\php_oci8.dll' in Unknown on line 0 Someone suggested to play with php.ini parameters specifying folders. I tried the following, without success: 1) setting extension_dir to C:\php and extension=php_oci8.dll 2) commenting out extension_dir and setting extension=C:\php4\php_oci8.dll 3) inserted dl("C:\php4\php_oci8.dll") into script 4) tried all the things above with standalone php.exe, in Apache with php4apache.dll and in Netscape Server with php4nsapi.dll As I see, not the dll placement is a problem. I thought that dll lacks some symbols, but I've checked php_oci8.dll with dependency walker - php_oci8.dll successfully finds oci.dll from my oracle 8.1.6 client on Win2000 and other DLLs it needs.Everything seems OK with dependency. php_oci8.dll I'm using is from download.swwwing.com. I also compiled both php4ts.dll and php_oci8.dll with the same negative results. Can someone help me to solve this riddle ?