Time And Date Change W Battery Removal On Samsung

[chingching]

Hi,

I have had this phone for more than 2 years with never this problem. (GT-I5503). When I remove the battery the date and time change. I've tried switching to automatically use "network-provided" values, but that does nothing either way.

My provider is AIS, 1-2 call.

I just noticed the time was changing to about 7 hours previously, so I changed my "timezone" to zero from +7, and that seems to fix it.

Is there an internal battery that keeps time, like a desktop PC ?

Thanks for any suggestions.