function remove($wsdl) {
		$filename = $this->createFilename($wsdl);
		if (!file_exists($filename)) {
			$this->debug("$wsdl ($filename) not in cache to be removed");
			return false;
		}
		// ignore errors obtaining mutex
		$this->obtainMutex($filename, "w");
		$ret = unlink($filename);
		$this->debug("Removed ($ret) $wsdl ($filename) from cache");
		$this->releaseMutex($filename);
		return $ret;
	}