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: 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 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 binder - it successfully finds oci.dll from my oracle 8.1.6 client on Win2000 and everything seems OK here. php_oci8.dll I'm using is from download.swwwing.com. I also tried to compile both PHP4 and php_oci8.dll with the same results. Can someone help me to solve this riddle ?