setInterval in bg.js just dies without error

Hello folks,

I am still trying to establish a stable rss reader, that looks for new items in the RSS feed every few minutes. Therefore I register the background service and set an interval for my checker function.

var timer = setInterval(function(){
    getNewArticleCount();
}, 1000*60*1);

As a first thing in the getNewArticleCount() function I call an API Info, so I know the function has been called.

So far, so good. But after several minutes (about 7 to 9 Minutes) the interval just stops working. No error, no nothing.

Nov 22 15:43:36 unknown UIKitApplication:com.luehrsenheinrich.xxx[0xe9a1][6698] <Notice>: [INFO] >> Keepalive 1
Nov 22 15:44:36 unknown UIKitApplication:com.luehrsenheinrich.xxx[0xe9a1][6698] <Notice>: [INFO] >> Keepalive 2
Nov 22 15:45:36 unknown UIKitApplication:com.luehrsenheinrich.xxx[0xe9a1][6698] <Notice>: [INFO] >> Keepalive 3
Nov 22 16:07:49 unknown CommCenter[17] <Notice>: No more assertions for PDP context 0.  Returning it back to normal.
Nov 22 16:07:49 unknown CommCenter[17] <Notice>: Scheduling PDP tear down timer for (343667569.162510) (current time == 343667269.162536)
Nov 22 16:07:49 unknown CommCenter[17] <Notice>: Client [com.apple.persistentconnection[apsd,61]] is telling PDP context 0 to go active.

The fun thing is, no matter after how many minutes I resume the app (it does not crash!), Keepalive 4 is called just before resuming or at the same time. (The keepalive counts to 5 and then starts over with 1)

Anyone ever encountered a similar problem?