lib/AmazonSNS.php
public function setTopicAttributes($topicArn, $attrName, $attrValue) {
		if(empty($topicArn) || empty($attrName) || empty($attrValue)) {
			throw new InvalidArgumentException('Must supply a TopicARN, AttributeName and AttributeValue to set a topic attribute');
		}

		$this->_request('SetTopicAttributes', array(
			'TopicArn' => $topicArn,
			'AttributeName' => $attrName,
			'AttributeValue' => $attrValue
		));

		return true;
	}
public function setTopicAttributes($topicArn, $attrName, $attrValue) {
		if(empty($topicArn) || empty($attrName) || empty($attrValue)) {
			throw new InvalidArgumentException('Must supply a TopicARN, AttributeName and AttributeValue to set a topic attribute');
		}

		$this->_request('SetTopicAttributes', array(
			'TopicArn' => $topicArn,
			'AttributeName' => $attrName,
			'AttributeValue' => $attrValue
		));

		return true;
	}
Set a single attribute on a topic

@link http://docs.amazonwebservices.com/sns/latest/api/API_SetTopicAttributes.html
@param string $topicArn
@param string $attrName
@param mixed $attrValue
@return bool
@throws InvalidArgumentException