Problem with file uploading

Hi, I face a problem trying to upload any filesize greater than 8MB. In php.ini file, I have already set memory_limit, max_execution_time and upload_max_filesize to required capacity. The message shown on web-page is as below : "The server encountered an internal error or misconfiguration and was unable to complete your request." Apache error log records : "Premature end of script headers : c:/devel/php/php.exe FATAL: erealloc():unable to allocate 5884001 bytes." Thanks, Nic.