Magpie Plugin version 1.3.4 to 1.4

I have been using magpie plugin v1.3.4 without any problems. However, after upgrading to v1.4 together with the EE 1.6.5 (and 1.6.6) I am having following error codes for certain feeds, especially the ones from Amazon product search feeds;

Warning: MagpieRSS: Failed to fetch 
http://.....
(HTTP Response: HTTP/1.1 302 Moved Temporarily ) in .....\system\plugins\pi.magpie.php on line 1390

Notice: Trying to get property of non-object in .....\system\plugins\pi.magpie.php on line 105

and hence breaks the page. I checked such rss feeds directly with different browsers and standalone readers. Feeds are OK. When I downgrade magpie to v1.3.4, all are back to normal again in EE.

My question is; What are the main differences between v1.3.4 and v1.4? If there is not any critical security and/or performance issue, I can live with v1.3.4. If there is, what could be the solution?