Apple iPhone 4 main parameters
Network: UMTS/HSDPA/hsupaare (850, 900, 1900, 2100 MHz)
Volume: 115.2 x 58.6 x 9.3 mm / 137 g
Screen: 3.5-inch IPS 16 million colors, 640 x 960 more touch screen
The CPU: apple A4 processor
Operation: unknown memory
Storage space: 16 GB / 32 GB
Bluetooth/Wi Fi: support.-
Camera: 5 million pixels (the Lord camera) VGA (front camera)
The time/standby time: 7 hours (3 G) / 300 hours

Apple iPhone 3 G S main parameters
Network: UMTS/GSM/GPRS/EDGE
Shell: grind arenaceous plastic material back cover
Screen: 3.5-inch TFT, 320 x 16 million color touch screen more than 480 points
The CPU: performance improved
Operating memory: 256 MB DDR Mobile
Storage space: 16 GB / 32 GB
Bluetooth/Wi Fi: support.-
Camera: 3.2 million pixels af, support video recording
Battery life: to enhance the ability 15%, 20%

Can not solve this problem now
but u can backup ur sms to the local
this：iMacsoft iPhone SMS to PC Transfer

Use guide to Copy sms from old 3GS to old iPhone4


I know we can transfer iPhone Contacts, Notes, Calendar, Music, Photos and Videos to my iPhone 3GS.But how can we backup our previous iPhone 3G SMS to iPhone 3GS?

First,if you jailbreaked your phone than it’s damn easy just SSH your iPhone 3G and Navigate to /private/var/mobile/Library/SMS and Save sms.db on your computer then follow the vice versa with iPhone 3GS just copy sms.db from your computer to iPhone 3GS /private/var/mobile/Library/SMS folder.

Here is the simple to follow steps to Restore SMS History from Previous iPhone to New iPhone. All you have to do is to copy SMS backup files from old iPhone back up folder to new iPhone back up folder.

Navigate to the iTunes backup folder
1.Windows User : C >> Users >> User Name >> AppData >> Roaming >> Apple >> Computer >> MobileSync >> Backup >>
2.Mac OS X User : ~/Libary » Applications Support » MobileSync » Backup.

In the backup folder there will be X number of folders according to number of phones you synced to your iTunes. For example i have two iPhone 2G and 3G so i have two folders named with 40 random hex characters. But i need to copy SMS from iPhone 3G so how do i identify?
To identify your particular iPhone backup sync both phones with 5 minutes of interval and note the time in your computer clock while syncing.
Now Sort the view by date–this will let you easily tell which subfolder belongs to which phone.
Now you knows the folder where your previous iPhone 3G backup is saved, so explore to that particular folder (iPhone 3G) and copy these two files to iPhone 3GS folder. Make sure you must synced new iPhone 3GS at least once so back up folder will be created.
3d0d7e5fb2ce288813306e4d4636395e047a3d28.mddata
3d0d7e5fb2ce288813306e4d4636395e047a3d28.mdinfo

More information: How to transfer SMS/Contact from iPhone 3GS to iPhone 4 or PC?.- Transfer all iphone files to Mac computer