After JB my Iphone 3Gs ...my battery would drain in less that half a day without even using it .... It would go flat over nite from say 80% charge. Anyway the last time i plugged the phone into Itunes it wanted to send a crash report so I viewed the details and I shall paste them below. I have since restored my phone and the battery is really good lasting 2-3 days ( I dont use my phone much ) but I loved the Jailbreak Options and Themes.
Low Battery Log.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>AutoSubmitted</key>
<true/>
<key>SysInfoMachineConfigKey</key>
<string>iPhone2,1</string>
<key>SysInfoSystemProfileKey</key>
<string></string>
<key>bug_type</key>
<string>120</string>
<key>description</key>
<string>Incident Identifier: 4933EBCA-1ADB-4EA9-AE8F-03DDCA1A7ACF
CrashReporter Key: 481fec390712f952582de2753766e08670e5f441
Date: 2009-09-06 01:43:04 +1000
OS Version: iPhone OS 3.0.1 (7A400)

apsd: com.apple.apsd-connectionestablish-push.apple.com NoIdleSleepAssertion == 255, held for 00:01:12

Hardware Model: N88AP
Awake Time: 00:00:00 (0)
Standby Time: 00:00:00 (0)
Partial Charge: 1
Capacity: 1
</string>
<key>displayName</key>
<string>LowBatteryLog</string>
<key>host_os_version</key>
<string>OS:Windows;OSBuild:2600;OSMajorVersion:5;O SMinorVersion:1;</string>
<key>name</key>
<string>LowBatteryLog</string>
<key>os_version</key>
<string>iPhone OS 3.0.1 (7A400)</string>
<key>version</key>
<string>102</string>
</dict>
</plist>


This is the main thing that I noticed
apsd: com.apple.apsd-connectionestablish-push.apple.com NoIdleSleepAssertion == 255, held for 00:01:12

Maybe the Phone was never entering a sleep mode/Idle Mode
I did my mates phone at the same time and he is having major battery issuse.

This is what I installed and in what order.
Cydia user Grapical
All Updates
Then SBSettings
Then Fake APN (Love This One)
WinterBoard
Mac Snow Leapoard Theme
Lock Calander
20 Sec Lock Screen
and WB Weather on Lock Screen
My mates is JB so if you have any suggestions as what to try as I think something is running keeping the Phone awake ..PS I dont have SSH installed and I do know that that runs all the time and If i did have it running SBSetting can toggle it off. I really want to JB my phone againg but I feel that the battery draing so fast is not good for the phone as something must be running .

I had read here that it is likely Push Notifications is on and running in the background.

The fix was to install any program that uses push notifications from the AppStore. This will bring up the Push Notifications setting in Settings. You can then toggle off the service.

Worth a try...

Ok I will try that and see what happens

Found on another forum:
SSHed in their iPhone and moved the APSD file from start up in: /System/Library/LaunchDaemons/com.apple.apsd.plist

The person moved it into a dummy file somewhere else.. and reset the iPhone (iphone still worked).


According to this person the battery definitely seem to last longer and it did not get warm.

I removed the activatemms2g patch, and put the APSD file in my documents; using iFile. Afterwards I recharged my iPhone last night, and let it sleep. This morning it was still at 100%! Previously it would be 80%-75%.

__________________
Gort! Klaatu barada nikto!
iPhone 2G with FW 3.1 and no MMS

Hay guys ...thanks for the Tip ...Installed Ebay ...the turned off Notifications and all seem really good...